I don't think there's always an even number of repeats of the lace pattern -- especially since you're increasing one stitch each time. So for row 1, you're doing the lace repeat over 10 stitches and over 20 stitches; in all cases, the lace repeat section starts with k1 and ends with k2, so I guess on row 1 you have:
10-stitch version: k1, k2tog yo k2, k2tog yo k1, k2
(which is a not-quite-complete second repeat)
but I'm not sure what you'd do for the 20-stitch version, since k1 + 4 repeats of the middle section brings you to 17 stitches used, and the next bit in the pattern is a k2tog but you then need to do k2.
...I'm not being much help here, sorry *grin*