You can also use Nextor that includes the driver for this interface. The main advantage is you can really use FAT16 partitions and they become fully mountable on PC/Mac without risk of corruption. You will also have access to many advanced DOS functions, and the possibility of mounting the DSKs.
Did you make a backup from the original ROM? As JIPE mentioned above the 2.4 and 2.5 firmware are not compatible with your interface. I can’t find the 2.1 version JIPE mentions. You could try flashing Nextor but there is no guarantee it will work (but it won’t make anything worse than it is. If it does not work you could ask JIPE to send you the 2.1 ROM.