you've marked TRConstraint as obsolete, however not all behavior has been yet implemented in new RTConstraint.
Namely methods from "public - resizing", "public - camera", and "public - aligning”.
You’re picky! Excellent! I think we need particular classes such as RTAlignment and RTResizing. We will work on this over the next two weeks.
Secondly I am not sure about the name of RTConstraint class>>child:parent: (Tudor also didn't like the name when he saw it. :)) I don't think the naming fits well into Roassal... maybe RTConstraint class>>on:backElement: ?
I have renamed it as on: aChildShape background: aParentShape
Cheers, Alexandre