A question I did not see posted out there: I have owned an MX 700 for a long while and now the screen is going out. So, after looking high and low, I settled on a MX 450. It is a bit tedious, but I am up for it and I have great macros from the 700 to reference so I won't have to reinvent the wheel.
But... it appears all the learned codes from the ISY99 and an old Pioneer receiver do not work. They have worked for years from the MX700, and they get do get "learned" and "saved" onto virgin soft keys on the MX450, but then when tested there is no response from either the ISY99 or the old Pioneer. I can learn codes for the Yamaha (also old, I am old), TIVO box, Apple TV etc.
One thing to note: Neither the ISY99 nor the Pioneer came with a remote. I found the discrete codes long ago from somewhere on the Remote Central site (pronto? Hex codes?) I was able to get them onto the MX700 way back through the now defunct universal browser on the MX editor. (not really happy about seeing this functionality go). Oddly enough, I tried learning codes from the MX700 for the TIVO box as well and the MX450 fails to pick those up as well. The MX450 picks up codes fine when broadcast from the factory remotes but not from the MX700. But the MX700 does control all components fine.
So I conclude the MX700 fails to broadcast codes only to the MX450?
I have not connected the MX450 to the computer for upgrades and have not downloaded the back up software.
Thanks for any insight you collectively may be able to impart. David