I got this working in GSC 1.52 with these steps
Make sure you have taken a backup of the files you delete/replace in these steps below. I take no responsibilty for you damaging your install
I also assume your are familiar with the GSC folder structures.
Firstly google and download this version of Java (jre-6u37-windows-i586) and a copy of rfDynHUD.
Install said version of Java Runtime.
Assuming you have a copy of rfDynHUD downloaded from somewhere...
1. Delete the DynHUD folder from your plugins folder that came with GSC 1.52
2. Delete DynHUD.dll from from your plugins folder that came with GSC 1.52
3. Delete TrackMapPlugin.ini from your GSC2013 folder.
Then from your
rfDynHUD archive you downloaded...
1. place d3d9_rfdynhud.dll and TrackMapPlugin.ini to your root GSC2013 folder.
2. Put the rfdynHUD plugins
folder into your GSC2013/Plugins folder
3. Put rfdynhud.dll into your GSC2013/Plugins folder.
Not sure if this matters but I renamed "GSC.exe" to "rfactor.exe" and ran the game once. Then renamed back to "GSC.exe"
(One of the pugins I used needed this step back in the day, it may not matter?)
That should be it. Use the editor to configure your HUD how you like it.
Remember to run the editor as Administrator.
I have been using it with the following steps for three hours or so of driving with no issues.
Final note, I use a motec telemetry plugin, and Motecs [ctrl+m] will turn off the Dynhud. Just press [M] again and it will come back. (Issue with Trackmap). I also assume you know how to turn off the vanilla ingame HUDs.
If anyone still struggles, let me know and I will post my working files
Hope this helps someone as others posts have helped me.