I have used graph paper to make bargellos. You can tape several together and color in what you want to get the design you want then figure out the rest.
When a program says it is not Windows 7 compatible it generally means that the company has not had it certified. Windows 7 has an awesome compatibility mode -- I am running programs that are 8 years old with no problem. That said, maybe someone on the forum has tried it.
Also, it has a 30 day free trial -- nothing would be lost if you try it and it does not work. Here is a link:
http://www.softexpressions.com/software/bar/