I'm actually working on my own CCG, "Wind and Water" (http://zigraphix.com), but I stopped in to see how far you've gotten with Werocia, as I'd like to implement Wind and Water on GCCG as well. I've looked at the Mtg and Metw sample scripts, and I can more or less follow what was going on, but I was hoping you folks would have more script samples I could look at. I guess you're not there yet.
One thing I'd like to suggest, from my own experience in developing Wind and Water, is that a paper mockup can go a LONG way toward helping you sort out the rules, generate cards, etc. The simplest sort of paper mockup you can make uses those perforated business cards. You can set up the info on each card in Word or whatever and print them out, or even hand-write them if you don't have that many ideas typed in yet, and keep creating them as you go. Don't worry about artwork yet, or fancy descriptions. You can even skip names for now, and just work with combinations of stats and generic names, e.g. "Creature 1". I found that the first couple of rounds with cards written in pencil on business cards REALLY helped me to solidify the game mechanics for Wind and Water. This made thinking up new cards a lot easier.
After the first round of playtesting (with a close friend who also plays a lot of games), I printed cards on plain cardstock and cut them apart, and tried playing the game with my kids. (My target audience is kids. You might try this with college students or whatever.) I immediately discovered more things that needed to be clarified and improved with the rules. If you don't want to spend all day cutting out cards (which takes a lot of time, even with a lever paper cutter), you might consider ordering perforated cardstock from http://perforatedpaper.com. The classic trading card size isn't one of their standard formats, but they'll do it custom for approximately the same price as their business cards.
I'm now in playtesting with local game and anime groups, and getting ready for a beta release this summer, with a "real" printing possibly in the fall or winter. I know you folks don't intend to create and sell physical cards, but my point is this: only now, after playing the game multiple times in paper, watching others play, and making lots of changes, do I feel it's worthwhile to try to program it into GCCG. GCCG is a great game software development tool, and about as easy to work with as I can imagine such a tool being, but it's not an easy place to start with a new game. Classic software game design references often suggest that it's best to start with a paper prototype, and I find the more I work on my own project, the more I agree with them. Especially as it seems from the forum posts that your development team is also in the process of learning to write scripts for GCCG, as well.
I hope this is helpful,