@frontgear I followed the Idiot's Guide to iMessage and it Works!!! Authorized it using 2 factor on my iPhone, and was able to send an iMessage from one of the phones I use for testing. HooYaa!!
One question, what updates are safe to install? I presume I can install the iTunes and Remote Desktop Client update?
BTW - I get the impression that when 'TRIM Support' says Yes, this just means it's supported.
I ran this in terminal: sudo trimforce enable - and now I think it's actually turned on. I think this because of an ars technica article stating that Apple didn't want to turn on TRIM for 3rd party devices and be responsible for any data loss.
One other thing. I was able to send an iMessage from my Mac, and it showed up on my iPhone just like I had sent it from the phone. But after setting TRIM enabled and rebooting, I got this dialog from the iMessage window that automatically opened:
Did you get this dialog? I can already send using this Mac, so ... I'm confused?