1) About a month at the dealership. That is just beyond sad.
2) They changed the PTCM and still dont know what to do - for a TOP not working and no cruise control? That is not just sad, it is pathetic.
3) No, Iv'e been on here since 2009 and am on my third Roaster, never have I seen any indication of such an issue with the BCM. Largely , the BCM is SMT techhnology, so "solder issues" are not likely. Of course, if you SEE fractured joints (probably around the pins of the connectors that the cables plug into) hten by all means reflow them. Just be DAMN careful you don't bridge paths.
4) The Cruise is entirely within the PTCM, cept for maybe the wheel speed sensors and, of course, the multi function switch.
5) Top issues are usually NOT that hard to diagnose. Most often, they are caused by the sensors (which are really just spst switches) in the top frame and divider catch.
6) Thinking that the two issues are caused by the same module may be why it is not fixed. I am trying to think of ANYTHING in the car that would, by itself, disable the top
and cruise control. I got nothing.
"No cruise control" is pretty simple to interpret, but "top not working" does not tell us enough to give you any advice. Do the windows go down when you release the D handle and push the top up away from the windshield frame? Do you get a 'beep' when you do so? Or, do you get a beep only when you press the button to move the top? Do you have any issues moving the top manually? Provide some more information and maybe we can help.
Manual Crossfire Roadster Convertible Top Operation - YouTube