I would take each section on the pattern and blow them up on a photocopier to the size I wanted. Then cut each section apart and add 1/4" seam allowance to the individual pieces. It sounds like a lot of work, but you'd get better accuracy that way, and if you use either heavy cardstock or plastic template sheets, you'd only have to do it once.
For example, if you want 10" blocks, the factor to use is 1.60.