Yes, you have a Total Control system. And yes, you are screwed.

Total Control software is NOT to be given out to customers, unlike the Complete Control software.
In order to use Total Control software, a dealer has to login to the software with their dealer login. So it is impossible for a consumer to use it.

You have 2 choices.
1) Considering how much money is invested, you could try and find a URC dealer that will program things for you at a reasonable rate.

2) Pull everything out. You make it sound like you plan on making regular changes to your system. Well that's your problem there, most people don't constantly change things in & out of their system - why would you do that? If you just like constantly playing around with new things, then you need to pull that system out. It is never going to be viable for you, since you can't program it yourself.

That SNP-2 is obsolete, a modern streamer to replace with it's own app, would be what you are looking for (SONOS, MusicCast, HEOS, BlueSound, etc.).
That DMS-1200 can be replaced with any modern multi-channel amp. Or use a powered streamer for each zone, taking care of the amp & stream box at once.
That DMS-AV was a piece of crap to begin with (IMO). And is now obsolete. Any modern AV receiver will get you up to date.

And finally the controls. Unfortunately we are living in a time where something as simple as good remote for everyone is impossible to find. There are a few companies that are coming out with products now, to fight this ever escalating price & software BS of the major control companies from yesteryear. But none are really there yet.
Your best bet (and since you already have some MX-890s) is to register an account with URC (links are in other posts on this forum), and get a fresh copy of CCP (Complete Control Program). URC allows consumers access to the software by signing up with the serial number on the remote.