Grannierose, My husband doesn't want to use Google Chrome... I don't want to use Windows 8-- but there you have it. My husband thinks Windows 7 will pass into history like all the others and he's making me get used to Windows 8 so I can move into the future. :-)
Regarding the block size, the tutorial says to sew a scant 1/4" seam. If you are cutting 5" squares, you won't get the 8 1/2" block if you sew 1/4" seams. I believe it doesn't compute! :-) Either cut your squares bigger or sew your seams smaller to solve the problem.
I don't have such a large square up ruler either. But you can use a 4" x 15" ruler (or whatever size long ruler you have) and use the lines on your mat to square up blocks too. You just have to move the ruler to cut each side.
Anyone having trouble sewing this pattern might like to think twice about the February Valentine swap. I made a practice block for that swap (using the tutorial for the D4P with a twist pattern) and found that with all the cuts and seams on the diagonal, sewing and ironing can be tricky because of all the bias edges! My block was more wavy than I liked.
Just a reminder... everyone is welcome, any skill level! :-) Have fun!