The Popcorn Diamond block works better with a second row of hdc in the beginning. If you use this suggestion then mark the second row of hdcs as the right side.
63 Squares: Block 41 Fan and Popcorn Revision
Block 41 needs another row at the end in order to make the border straight. Last Row: ch 4, 2 tr, dc, 2 hdc, 3 sc, 2 hdc, dc, tr, dc, 2 hdc, 3 sc, 2 hdc, dc, 3 tr.