I've built an FF2e (NeoDemiforce translation with graphics glitch removed) out of a metroid cart (I battery-packed the cart) and a maniac mansioncart . I''ve tried building FF2e using ultima carts but I used a bout 9 carts and not one of them worked. I may have programmed them incorrectly but I don't have anymore ultima carts to figure it out. Anyway, I do believe an SNROM-05 board should be fine. Check the proper soldering of all of your data lines. Also make sure you have properly rewired the eprom (using a 27C020 you only have to modify 4 pins with 30 AWG wire) Anyway, good luck with the mods.
Programmers dont die they just GOSUB without RETURN...