Well, technically, if you use SCI Studio to make your game and freeSCI to run it, there's nothing exactly stopping you from distributing your games, and, erm... selling it commerically. However, the template does use my code which I built from reverse engineering Sierra's, so it's not 100% in the clear for commercial use. Well, let's just say, if Sierra wanted to, they could attack. Also, if you do that, and don't give a percentage of your profit to SCI Studio and FreeSCI, you're not going to be on anyone's good books. hahaha
I'd hate to see someone making a game with SCI Studio make more money than SCI Studio, lol!
I really like open source/free software, as do 99% of the population. Make your game for enjoyment, not to try and make money. No offense, but I seriously doubt many (or any) would pay for a homebrew EGA adventure game. With so much for free on the internet today, be it software, music, movies, etc. very few people will pay for something they don't need to. For example, there are hundreds of freeware adventure games already.