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.

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.