: I redid my main outside plumbing area just before the line goes into the house and
: also ties into an irrigation line. I had two regulators and two ball
: valves. Problem is when I fired it up, the connection into the house and an
: ajoining 90 are leaking. If I have to remove them and resweat, I will have
: to take half of my assembly apart. Are there any tricks to repair a leaking
: connection. Would reheating and applying some solder around the joint
: help???

The fittings will need to be removed and refluxed.
When soldering around PRV's and valves, it's important that the expanding hot air has a place to go. Otherwise, the air will blow a hole in the soldering job.

: Also, on one end of the assembly there is a regulator and as a result,
: unless I set a post underneath the setup it leans. Is it within code to use
: a post or strap part of such an assembly to anjoing wall such as a fireplace
: to stabilize it?

Whatever it takes is okay. Pipe inside is always strapped. Just make sure that no copper makes contact with the fireplace brick or concrete. You can use a UPC plastic tape on the copper for protection.