usergroup promotions question?

[USAMustangs.com]

I appreciate your reply.

I'm basically wanting to move relatively inactive users to a special user group that I set up that opts them out of the mass PM's I sent out periodically. My custom usergroup is Registered Users Mass PM Opt Out.

So, I'm wanting the Promotion system to move (demote) a Register User to Registered User Mass PM Opt Out after a year of 50 posts or less.

How would I set this up using the Reputation method?

And since I have had Reputation disabled all of this time. I have now enabled it in AdminCP. What is the query that needs to be run to bring every member's reputation back up to what it should be based on their current stats? Because Rebuilding User Reputation in Update Counters doesn't work.

Thanks