I had a crash and found that the fuel lines were damaged, much easier than I expected. Granted I don't have tons of experience, but what you explained sounds like the engine is running lean (wants to quit when you climb, not getting to full RPM), which could be happening as more air is getting in (or fuel escaping) through a leak somewhere.

My OS has been more forgiving than a fairy godmother. It's ran lean, rich, in different conditions, etc. while I was still learning how to tune. Your's is supposed to be more reliable and forgiving than mine, so I'd start with the fuel lines.

Good luck.