it should be totally expected ;o
It shouldn't since its Java and the community of Rm started with RGSS. But I guess they are quickly shifting to Java.
A change of programming language isn't such a big deal as far as "re-learning" scripting goes. Except for the more esoteric or machine level languages, there's really no big deal in switching languages, it's not like it makes you need to re-learn everything from scratch or anything like that. The fact that the engine kept the same general logical structure that it had on VX Ace is much more relevant, in this regard.
I imagine several action battle systems are in development. It's just that they probably can't be finished in like a week if you have other arrangements to meet.
Separate names with a comma.