After upgrading from windows 7 to windows 10, I copied out the mpv.dll from the OFS 2, installed OFS 3.2, renamed mpv-2.dll to mpv-2.dll.old, copied in the old mpv.dll and renamed it to mpv-2.dll, and it works without crashing.
… now if I can just get it to import a funscript made by another tool (scriptplayer.videosync.exe).