Looks cool. I'd have to agree on that .60 for power. At least a .90-.120. You may not use it all, but boy, it's sure nice to have in a pinch. At 86" it's a pretty fair sized plane. I know lots of guys flying Extras and Sukois around that size and only 1 has used the recommended .60 for power. Just not enough for the size and weight. I know they're aerobatic planes, and use all the power(on a regular basis) but you're going to have to be careful with weight with a .60.

As for the windows, vacuum formed. Lots of articles and drawings for boxes around. It looks like it'll be a great plane when it's done -keep the drawings/pics coming.