RPG creation software, Part 1

I've been testing out a few programs for creating RPGs trying to find one that will work best for the way I do things and I thought I'd share what I've learned.  All are free and have active communities, all are 2D based, all run on windows and one also runs on Linux and Macintosh.  I chose four programs to test, the others got axed before download because of things like not being free, having an unfinished engine or being in development limbo.

If you have a suggestion for software that I've missed and should look into, send a link.  Keep in mind that it must be free and complete enough that I can make a small game with no money involved, and it can't be a Mac only product (because I don't own a Mac).  Please note that I'm not interested in general game makers unless it's got some sort of built in RPG template.

As I test these out I'll be creating a small game and which I'll make available to play at the end.