Does this literally mean skipping like a light run/trot? Or can it be used as in "skipping lines" or "you skipped a spot"

This is borrowed from English and has the same range of meanings.

From 'Geiriadur Prifysgol Cymru' (University of Wales Dictionary) = 'to skip or jump' (ie physical motion) and 'skip, miss, omit' (ie activities, comitments, tasks, obligations etc).

Criw o rai rhyfedd maen nhw'n.