Looking for a macro to scan a group (or raid) for debuffs and cast RGC if a debuff is found. I've typically been able to make minor edits to macros to get them to work, but completely clueless starting from scratch! Does anyone have a macro that fits what I'm looking for they would be willing to share? Thanks.

I'm not terribly familiar with what is out there, I never used anyone else's macros, but I can almost guarantee one of the big box solutions (if not all) have some segments that do what you want. Reviewing how those work might be all the inspiration you need to write a simple solution.