I've been testing as well and have found issues with launching a few standalone emulators -- c64.emu, Redream, and PPSSPP. PPSSPP launches but won't load game.
I've also been testing arm64 Retroarch cores and these don't seem to work (for me): freeintv, snesx, flycast, and mupen64plus_next_gles3.
I've hit a crash issue with a Cave theme that worked previously. It uses a background.swf causing a crash (and may be raising a 64b issue).