rg99: update docs

docs/manual/platforms/rg99.md

@@ -2,13 +2,22 @@
 
 ## Installation
 
-**Requires a recent OpenDingux beta**
+**This version is experimental and requires using an unsupported fork of OpenDingux!**
 
-1. Copy [devilutionx-rg99.opk](https://github.com/diasurgical/devilutionX/releases/latest/download/devilutionx-rg99.opk) to the apps directory.
+1. Install the OpenDingux fork from https://github.com/od-contrib/buildroot/releases
-2. Copy `diabdat.mpq` from your CD, or GoG install folder to:
+2. Copy [devilutionx-rg99.opk](https://github.com/diasurgical/devilutionX/releases/latest/download/devilutionx-rg99.opk) to the apps directory.
+3. Unpack and minify all the MPQ contents using `unpack_and_minify` from https://github.com/diasurgical/devilutionx-mpq-tools/.
+4. Copy the resulting directories to:
 
    ~~~
-   /media/home/.local/share/diasurgical/devilution/diabdat.mpq
+   /media/data/local/home/.local/share/diasurgical/devilution/
+   ~~~
+
+   You will need to symlink `/media/data/local/home/.local` to your SD card first:
+
+   ~~~
+   mv /media/data/local/home/.local /media/sdcard/dotlocal
+   ln -s /media/data/local/home/.local /media/sdcard/dotlocal
    ~~~
 
 ## Controls