It looks like someone designed the batch file to run on Windows for a GOG version of Ultima VII and hardcoded the installation directory path for the game.
"Patches" for DOS games should be designed for DOS not for install from Windows and also for the original version of the game too, IMO
You can either ask the author to fix the script, fix it yourself or manually perform the actions the script does.
Confusingly the script states "Do you want to play the original DOSBox version", which to me implies an unaltered version of Ultima 7 (well GOG version anyone) which should mean the script shouldn't have to do anything but does appear to modify the install so 🤷

Really you should be playing Ultima with Exult and if so and you want to use this "patch" then just manually do what the script does which appears to be copying files into the mods folder.

the GOG version of the game runs in dosbox--no choice. ultima 7 uses a voodoo memory manager which MUST run in real mode dos. thanks, i'm sure exult if fine, but my aim at this point is not playing the game, but rather trying to learn something, ostensibly really simple, that i didn't know how to do on the dos command line.

the script won't even run regardless if the installation path is correct or wrong. "illegal command" error is all i get...nothing else echoed to the screen. the file extension is cmd, not bat. i assume that has some significance?

Well the script is designed for Windows command prompt not DOS but mostly could be used in DOS if someone wanted to.
.cmd and .bat can both be used in a NT based OS to run batch files.
So you need to figure out if you want to run the script in Windows or DOS (with or without LFN) and then account for that.
There is nothing preventing one script from running in both if designed to do so.

These two patches are what I use on my real DOS PC

Ultima VII Frame Limiter Patch

U7DCP - Ultima VII DOS Cache Patch

aha, that was the piece of information i was missing. i did not realize that the .cmd extension is an NT cmd script. the last time i had windows installed on any of my PCs was over 10 years ago so i was oblivious trying to run the script in dosbox. i spun up a windows xp virtual machine and the script ran immediately. everything in the .cmd script looks similar to what i currently have in my own msdos 6.22 autoexec.bat file so i assumed it was for dos (i even tried the msdos 6.22 command.com with 'ver set' in dosbox trying to get the script to run). thanks for your help.

hey, i haven't seen those u7 specific patches before. will have to check them out.