RE: v.to.rast failure

You could try:
1) v.digit command=> option E (edit) and sub-option t (to re-type a lyne)
                     and next,
                     option L (to label areas (sub-option a)
2) r.compress
3) r.support
4) d.rast

Possibly it wil work.
Roberto de Souza
Department of Earth Sciences - Open University
Milton Keynes - England