Hi rujasu, thanks for the compliments.
I am also a long-time RPG and somewhat-long-time OSS enthusiast. One of the reasons I started this project was because I felt the exact same way as you: there needs to be some decent single player RPGs for Linux.
If it makes you feel better, I had never used SDL and never even heard of Lua until I started working on Allacrost.
The last two years have been a lot of learning for me, but I've come out a much, much better programmer because of it.
I'm glad you would like to help out. I have no idea if you would be interested, but our code documentation in the wiki needs a lot of updating. But if you'd rather code, that can be arranged as well. In any case, hope you'll stick around with us.