So, you are seeing the constraint warning when you bump up against a constraint but you are not fixing the issue? Are you selecting "don't tell me about this again?" If so, you'll need to re-set the planning wizard. Go to File > Options, Advanced and make sure all of the options under the Planning Wizard are checked.

That being said, you are correct, the planning wizard will not continually warn you about missing the same constraint until you resolve the issue with the first constraint. The constraint is already violated, so no further messages appear. Not sure what registry edits you made other than renaming the Options key, restarting Project will re-create the options. Are you up to date with patches for Project 2010? Check:
https://blogs.technet.microsoft.com/...pport/p/msp10/