This part alone almost made me crazy. There is a compatibility hack in sdl2 to stay compatible with sdl1 so that it never returns the device id 1 on success when opening an audio device ! So it means you must ignore the returned device id (if using something else than autodetect).
Crazy stuff... I'll fix that ASAP... It's changed in sdl3, it correctly returns the logical device id which was opened, I guess sdl3 is soon now. I would have spotted this earlier if I hadn't changed my installation here, no 2nd audio card to test... oh well... !!!
Ok, fixed. The autodetection is totally different now, it can't rely on opening the device as it did before, so it might work better for you now. Tested in many configurations, it should be ok everywhere.
For the neocd bios, yes it looks for neocd.zip in the raine directory, it can't look anywhere else since there are no roms directory in neocd. It's always been like that.