Now I am seeing that the gap should be .032

Would this cause it to not run right if I left them stock out the box at .029?

Actually, BKR6EQUP is the correct plug for your engine.

Here is some more info on the error code: P0305 Bmw Misfire Cylinder 5 OBDII Engine Light Trouble Code | Engine-Codes.com

I think your next step is to replace the CCV. You need to make sure it's not dumping oil into the intake tract and/or causing a vacuum leak.

Decided to buy the stock plug last week and changed them out. So far so good. No codes and my wife drove it all last week to work without issues.

The Iridiums didn't work well for my X5. Bought BKR6EQUP. We're good now. Next is to change out those subframe bushings now.