I don't have any recommendations, but about a year ago I was doing some modifications to a site which had used phpForms, and ended up spending many hours figuring out the quite bizarre (at least in my opinion) database scheme it uses, and then more hours figuring out how to get the application I was developing to integrate with it. If you plan to just use it "out of the box" and never need to work with its underlying database, then this may not be an issue for you.