Hi Juan,
Let's say that your pose of the situation is so far besides what I had in mind, that I better explain from scratch. So I am actually not responding to your post, OK ?
If you upgrade XXHighEnd you always and ever do that for the PC you will be running it on. If that is the Music Server PC, then you install it there (in its Operating System Environment, which normally is Drive C: (better read this as : *always*)). If that is the Audio PC, it is not different : again you install this in drive C:, always.
In the RAM OS Disk there is one small exception : don't install it in C: when you are booted from RAM currently, because now C: is RAM and this is volatile (will disappear at the first reboot). Solution : Boot into the BASE of the OS of concern. There again you have Drive C: but now it is your harddisk and now nothing will be lost at a reboot.
This should make it clear, but with the notice that this should have been clear for a long time, or otherwise it will always be a bit guessing for you of what will happen :
BASE = HDD/SSD = Permanent storage.
1*) Boot from RAM means : BASE is copied to RAM and from there the OS boots.
Change an OS setting in a RAM booted OS, and you will lose that again at the next reboot. So, useless.
Change an XXHighEnd setting in a RAM booted OS *is* preserved because XXHighEnd asks you to mount the BASE "disk" and if you do, changes are saved to the BASE.
Effect ? go back to 1*) and you will understand.
Answer to the question "where must I put the upgrade ?" -> a. Always on C:.
b. Always on C: of the PC of concern (where you want to use the new version);
c. Never on a RAM booted OS because you will lose it at the first reboot.
Side note :
Yes, we can access "the other OS environment" on Drive D: as well, just the same as we can access each BASE OS via drive X: after it has been attached by XXHighEnd.
But this is way out of your leage as long as the basics are not understood.
And I am not saying it is all very easy ...
Peter