As promised, I am reporting back on my experience...

My flights for the day...

BKK-HKG, HKG-MLE, MLE-HKG, HKG-ORD (Yes these are all back to back)

The very nice agent in Bangkok was able to print all boarding passes and all lounge invites in Bangkok, despite these being on three Itineraries.

As others reported, this was easy. There was no line for transfers. The guy there kept pointing me to customs (just getting off CX601) and kept pointing to transfer. It helped a Cathay employee was there. I handed him my boarding card. He made a phone call (about 1 minute) and then asked if I had my lounge card. I said yes, and we were off to security.

5 minutes later, I was in the lounge. Piece of cake.

As others have stated, at a minimum, have a printout of your flight info. Having your onward boarding card is a nice bonus.

I have this "turn" scheduled two more times in the next few months. I can breathe some relief now.