Hmm I don't know how comfortable you are with things like this, but this should be the easiest way to do this. Using a hex editor, copy the first 192 bytes from a rom that supports rumble (Drill Dozer probably) onto the first 192 bytes of the Apotris rom. This should be the area you're replacing (up to and including the B0 row):
Though I'm pretty sure this would work, I can't test it myself so I can't be certain.
As for the cartridge, insideGadgets will definitely have more stock some time in the future! Seems like there's a part shortage unfortunately. You can also give your email to the store to be notified when more stock is available.
It works like a charm! Thank you! It certainly feels a bit gimmicky though, but it's still a nice addition to have.
I just registered at insidegadgets. Can't wait!
