OK, it is 5 am here, and last night I had been thinking on this. The other thing the teacher had us change was to make the first cut of the background fabric a 4 1/2 square, which then gets sub cut to a triangle. (well the pattern called for a 4 3/8 square, sub cut to a triangle)
I am going to make one more block using the cut recommended in the pattern, and see what happens.
Could it be that simple!