Thanks to all for the suggestions. Unfortunately, transmission (which seemed to be in good shape a few weeks back) went out. So we will get that rebuilt first. No advance notice on this one - dealer shop said the aluminum sprockets inside were shot?? Entire rebuild about $1800. I think I am going to own this Jeep for awhile. :-)
As far as CEL issue, dealer shop's official response is they isolated to the cat - everything else (sensors, wiring, PCM, etc...) is fine - so once I get jeep operational I will have cat replaced again by Jeep aftermarket shop that installed it. Hoping that will do it.
I will keep our progress posted as perhaps it may help others out there in the future.