I too, have a very complex system with over 70 units in it. Restarting was not a solution.

I have not tried the VMware solution yet.

The solution for me was to create a dual boot machine. 2 Drives. 1 for XP and 1 for new OS's. Default is Windows 8.1, but starting using the Boot menu at start up I can start it on another drive which I loaded Windows XP 32 and updated to SP3 which you will be able to do for quite some time yet. Just nothing new updates. This way you have the best of both worlds. I have many other applications which would not run on Windows 7 or 8.1 which are required for my system. The vendors are long gone. One is Tunebasic for running my 16 Denon DRD-1400 CD 200 disk changers. This allows me to continue using the 3,200 CD's
Load Windows 7 or 8.1 on your machine and get it going the way you want.
Add the 2nd drive and unplug the Windows 7 or Windows 8.1 drive while you load XP on the new drive. Once you have is working, you can shut it down, Plug the Windows 7 or 8.1 drive back in and restart. Both OS's will be available depending on which you set as the default in Bios, or from the Boot Menu.
Just make sure you don't have both drives plugged in at the same time when loaging XP to make sure you don't corrupt something on the 7/8.1 drive

I have seen where you add a boot file which brings up a menu at startup to select which you want to use, but haven't researched that yet