Several levels get skipped when progressing normally; it skipped levels 13, 17, 21, 23, and 24 for me, forcing me to replay them from the level select menu. Collecting stars for said levels doesn't work and ends up collecting them for a different level, and sometimes clicking levels in the menu takes you to the wrong level as well. It looks like level sequencing was altered during development and that wasn't consistently handled in the menus and level-end code, or something along those lines.
Anyway, decent puzzles other than that hiccup, but I'm not sure the level designer actually solved his own puzzles optimally. Levels 3, 4, 6, 7, 8, 11, 14, 15, 22, 24, and 25 are clearable in fewer moves than par. (Assuming those numbers are correct, due to said level selection glitches. There also seemed to be one level that I couldn't find ever again in level select, though it's possible I'm misremembering that.)
Updated score now that the level-selection glitch appears to be fixed. (Also fixed the list of below-par levels up above, now that the level select screen's working properly for me.)
The solution space is pretty small, so you could just build a brute-force tester to calculate pars for most levels. Even a 7-move solution has less than 280k options. I do understand the point about screen-warping not having been introduced before level 9, though; I guess that's a matter of opinion, but it seems to me that a par score should be as optimal as possible, encouraging people to come back later once more mechanics are learned. Up to you.