Are the frames sent out of order? And where might one such as my self find the specifications for the checksum algorithm used by the protocol, Or is it just the internet checksum algorithm of RFC1071 broken down into 2 bytes?
The frames seem to come 3, 2, 1, 3, 2, 1, 3, 2, 1,… on my controller.
I don’t think you can use the checksum, unless you reverse engineer it. You could ask IFI, but I doubt you’ll get much.
As soon as I get a chance, I plan too. 
[Included in my revision of the dashboard control is a little window that has the packet bytes. I plan on using it to figure out OI from RC]