I think it's a good idea to get the battle system done. Don't forget the in-game menu afterward, except of course the save function. That's what I always did while coding RPGs, or sometimes I started the menu then battle engine.
Glad you got some progress though. You should put your code in the C forum or maybe PRIZM hacking forum, in a CODE tag, if you need help, because in project threads many people who only look at help topics will not notice.