That sound setup looks similar to Tiger Sonic, where one of the S pins is used for sound effects(at higher volume than music)
What are the resistor values on S3 and R here?
Oh, I forgot that the piezo is controlled by a transistor on the mainboard, so the resistor values don't matter here.
Batman Forever is added and working. I emulated the SM512 already when I added SM511, but it was completely untested until now, fortunately it works well.
1 correction for rzbatforraw.bin: offset $C04, change $FF to $EF.