diff --git a/docs/rp412-controls.html b/docs/rp412-handbook.html
similarity index 95%
rename from docs/rp412-controls.html
rename to docs/rp412-handbook.html
index 864f52a..8e5c122 100644
--- a/docs/rp412-controls.html
+++ b/docs/rp412-handbook.html
@@ -1,4 +1,4 @@
-<title>Red Planet 4.12.7 — Controls</title>
+<title>Red Planet 4.12.7 — Handbook</title>
 
 <style>
   :root {
@@ -755,12 +755,13 @@
 
   <header class="masthead">
     <p class="eyebrow">Virtual World Entertainment · Tesla pod · RP 4.12.7</p>
-    <h1>Red Planet<br>Controls Map</h1>
+    <h1>Red Planet<br>Handbook</h1>
     <p class="lede">
-      Every input the pod answers to, on the gamepad and the keyboard. The
-      keyboard is the pod's button board: the letter and number rows are the
-      MFD banks laid out as they are printed on the panel, and flight moved to
-      the number pad so the board stays free.
+      Every input the pod answers to, on the gamepad and the keyboard, and
+      every file it keeps beside the exe. The keyboard is the pod's button
+      board: the letter and number rows are the MFD banks laid out as they are
+      printed on the panel, and flight moved to the number pad so the board
+      stays free.
     </p>
     <p class="provenance">Generated from the default <code>bindings.txt</code> · all of it rebindable</p>
   </header>
@@ -1312,10 +1313,90 @@
     </div>
   </section>
 
+  <section>
+    <h2>Files beside the exe</h2>
+    <p class="sub">
+      Four files in the game folder are yours. Only one of them ships — the
+      game writes the other three when it first needs them, so a fresh unzip
+      has none of them and nothing is lost by deleting one.
+    </p>
+
+    <div class="tbl-scroll">
+      <table>
+        <caption>Yours to edit</caption>
+        <tbody>
+          <tr>
+            <th class="mono">environ.ini</th>
+            <td>
+              Every engine option, commented in place — displays, renderer,
+              Steam, the podium, the lot. The only one that ships, and the one
+              to read first.
+            </td>
+          </tr>
+          <tr>
+            <th class="mono">bindings.txt</th>
+            <td>
+              Every key, pad button, axis and joystick row. Written with the
+              full documented default layout the first time the game runs.
+            </td>
+          </tr>
+          <tr>
+            <th class="mono">pilot.cfg</th>
+            <td>
+              Your callsign and loadout, saved on the way out of the setup
+              screen so they are there next time.
+            </td>
+          </tr>
+          <tr>
+            <th class="mono">mfd_layout.cfg</th>
+            <td>
+              Where you dragged the windows, and the <code>,noframe</code>
+              flag. Only written when <code>RP412MFDLAYOUT=save</code>.
+            </td>
+          </tr>
+        </tbody>
+      </table>
+    </div>
+
+    <div class="callout">
+      <p>
+        <strong>Two that catch people out.</strong>
+        <code>environ.ini</code> is applied <i>over</i> the environment, so a
+        variable you set in a shell loses to an uncommented line in the file —
+        comment the line out rather than fighting it. And
+        <code>bindings.txt</code> is never overwritten once it exists, which
+        is what protects your edits: after an update, <b>delete it</b> to pick
+        up new default bindings.
+      </p>
+    </div>
+
+    <h3>The rest of the folder</h3>
+    <p class="sub">
+      Shipped data the engine reads. Nothing here is meant to be edited, but
+      it is worth knowing what is what.
+    </p>
+
+    <div class="tbl-scroll">
+      <table>
+        <caption>Engine data</caption>
+        <tbody>
+          <tr><th class="mono">RPDPL.INI</th><td>Renderer and scene configuration. Named by <code>L4DPLCFG=</code>, so it can be swapped.</td></tr>
+          <tr><th class="mono">GAUGE\L4GAUGE.INI</th><td>Gauge canvas pages. <code>L4GAUGE=</code> picks one by name — a name that is not in here switches the MFDs off entirely.</td></tr>
+          <tr><th class="mono">GAUGE\L4GAUGE.CFG</th><td>The gauge layout data that page points at.</td></tr>
+          <tr><th class="mono">AUDIO\AUDIO.INI</th><td>Sound banks. <span class="mono">AUDIOMR.INI</span> is the mission-review twin.</td></tr>
+          <tr><th class="mono">JOYSTICK.INI</th><td>The 1995 single-stick calibration, for the legacy <code>L4CONTROLS=DIJOYSTICK</code> path only. Modern sticks are configured in <code>bindings.txt</code> — see above.</td></tr>
+          <tr><th class="mono">*.CFG <span style="color:var(--ink-quiet);font-family:var(--sans)">in AUDIO\</span></th><td>Pod audio-hardware mixer tables. Dead weight on a desktop; kept because the arcade path still reads them.</td></tr>
+          <tr><th class="mono">RPL4.RES</th><td>Resource blob, not text.</td></tr>
+          <tr><th class="mono">steam_appid.txt</th><td>Steam runs under Spacewar (480) until Red Planet has its own AppID.</td></tr>
+        </tbody>
+      </table>
+    </div>
+  </section>
+
   <footer>
     <span>Red Planet 4.12.7</span>
     <span>gitea.mysticmachines.com/VWE/RP412</span>
-    <span>docs/CONTROLS.md · CONTROLS.txt ships with the game</span>
+    <span>docs/rp412-handbook.html · HANDBOOK.html ships with the game</span>
     <span>RGB keyboards mirror the pod lamps · RP412KEYLIGHT=0 to disable</span>
   </footer>
 </div>
diff --git a/pack-dist.ps1 b/pack-dist.ps1
index 5cbac6f..a76babe 100644
--- a/pack-dist.ps1
+++ b/pack-dist.ps1
@@ -9,7 +9,7 @@
 #    - libsndfile-1.dll beside the exe; OpenAL32.dll copied from the system
 #      when installed, with oalinst.exe included as the fallback installer
 #    - a desktop environ.ini (PAD;KEYBOARD controls, on-screen plasma)
-#    - start-windowed.bat and a README
+#    - start/joyconfig scripts, HANDBOOK.html, CONTROLS.txt and a README
 #
 #  Usage:  powershell -ExecutionPolicy Bypass -File pack-dist.ps1 [-Zip]
 #
@@ -81,9 +81,8 @@ foreach ($file in 'RPDPL.INI', 'JOYSTICK.INI', 'RPL4.RES', 'TEST.EGG',
     Copy-Item (Join-Path $assets $file) $dist
 }
 
-# The controls map travels with the game (players get the diagrams
-# without needing the repo). Flattened to ASCII so it reads correctly
-# in Notepad - the markdown source keeps its typography.
+# The controls half as plain text, for Notepad. Flattened to ASCII so it
+# reads correctly there - the markdown source keeps its typography.
 $controls = Get-Content (Join-Path $root 'docs\CONTROLS.md') -Raw -Encoding UTF8
 foreach ($pair in @(
         @([char]0x2014, '-'), @([char]0x2013, '-'), @([char]0x2018, "'"),
@@ -93,17 +92,18 @@ foreach ($pair in @(
 }
 Set-Content -Path "$dist\CONTROLS.txt" -Encoding ascii -Value $controls
 
-# The same map as a page, for anyone who would rather look at the
-# diagrams than read them. Its source is the published artifact, which is
-# a fragment - the publisher supplies the document shell - so wrap it to
+# The handbook as a page: the controls map with the diagrams, plus the
+# joystick setup and what every file in the folder is for. Its source is
+# the published artifact, which is a fragment - the publisher supplies
+# the document shell - so wrap it to
 # stand alone: without a doctype the browser drops into quirks mode, and
 # without a charset the typography arrives as mojibake. Written without a
 # BOM so the charset declaration is the only thing speaking.
-$controlsPage = Get-Content (Join-Path $root 'docs\rp412-controls.html') -Raw -Encoding UTF8
+$handbookPage = Get-Content (Join-Path $root 'docs\rp412-handbook.html') -Raw -Encoding UTF8
 # Stamp the shipped copy with the build's own version. The source keeps a
 # readable one for publishing; only "4.12.<n>" is touched, which on this
 # page is always the version and never anything else.
-$controlsPage = [regex]::Replace($controlsPage, '4\.12\.\d+', $version)
+$handbookPage = [regex]::Replace($handbookPage, '4\.12\.\d+', $version)
 $page = @"
 <!doctype html>
 <html lang="en">
@@ -112,12 +112,12 @@ $page = @"
 <meta name="viewport" content="width=device-width, initial-scale=1">
 </head>
 <body>
-$controlsPage
+$handbookPage
 </body>
 </html>
 "@
 [System.IO.File]::WriteAllText(
-    "$dist\CONTROLS.html", $page, (New-Object System.Text.UTF8Encoding $false))
+    "$dist\HANDBOOK.html", $page, (New-Object System.Text.UTF8Encoding $false))
 
 # --- OpenAL runtime --------------------------------------------------------
 # The exe links OpenAL32.dll (32-bit). Prefer shipping the already-installed
@@ -476,9 +476,24 @@ environ.ini is self-documenting: every option ships in the file with
 a comment (Steam networking, keyboard lighting, stick inversion, LAN
 hosting, developer keys, display scaling and radar placement, and more).
 
-CONTROLS.html is the full controls map - open it in a browser for the
-pad, keyboard and pod-panel diagrams. CONTROLS.txt is the same thing as
-plain text.
+HANDBOOK.html is the full manual - open it in a browser for the pad,
+keyboard and pod-panel diagrams, the joystick setup, and what every file
+in this folder is for. CONTROLS.txt is the controls half as plain text.
+
+Four files here are yours. environ.ini is the only one that ships; the
+game writes the rest when it first needs them, so deleting any of them
+simply starts that part over:
+
+  environ.ini      every engine option, commented in place
+  bindings.txt     every key, pad button, axis and joystick row
+  pilot.cfg        your callsign and loadout
+  mfd_layout.cfg   where you dragged the windows (RP412MFDLAYOUT)
+
+Two that catch people out: environ.ini is applied OVER the environment,
+so a variable set in a shell loses to an uncommented line in the file;
+and bindings.txt is never overwritten once it exists, which is what
+protects your edits - so after an update, delete it to pick up any new
+default bindings.
 
 Known prototype notes: pods race untextured (the player1-8 skins come
 from the presets system, not shipped data), and text drawn on the plasma