[Chemlak]

Since you've taken the big plunge and snagged CC3+, I'd first like to welcome you to the ranks of insane GMs who buy software just for gaming, but I'd also like to strongly recommend the Tome of Ultimate Mapping for use with CC. It's (surprise!) a bit of money, but is a complete set of documentation, a comprehensive guide, and has some truly fantastic handy-dandy tips and tricks that the CC3 manual doesn't cover.

Next: work through the tutorial in CC. This is not a piece of pick-up-and-play software. You're already aware of the learning curve (and I'm glad it hasn't put you off), but the tutorial walks you through things brilliantly. I'd recommend doing all of the tutorial before even trying your own map. It teaches you good habits you won't learn if you just jump in.

Good luck!