You're almost there! Your disk images are fine, but it sounds like there's a problem in the connections between the Mac floppy connectors and the CPLD, have you re-checked those? In particular, check PH0 through PH3, /WREQ, SEL, /ENABLE.EXT, and RD for opens or shorts between neighboring traces, for both connectors and the CPLD.

The Mini vMac "blank" images may have been read-only files, which is why you see the lock icon. Put the SD card in your PC, and clear the read-only flag for all the files.