Hey Jeff,
I was able to do this finally. Once you have done the downloaded and exported into a file, which is what I did, you then transport that file whatever way you want/can into your isolated system as a directory. In other words... you have on your UMDS machine, after export, a directory named "whatever" with a folder named "Hostupdate"(this contains all the updates), a file named "version1.txt", and another file named "version.txt". Now you need to take the folder called "whatever" and copy that to the system drive on the vm/physical machine that your Update Manager is on. Then go into Update Manager and then clik on the Configuration tab. Choose "Patch Download Settings", unclik "Direct connection to Internet" and clik "Use a shared repository". Now put in the path to the folder you just moved to the system drive. In my case it was c:\patchesx4. Last step, clik "Download" object to the right of path statement. It should say "connected" afterwards.
My export file was very large so I found that you can delete any updates in the folder "Hostupdate" that you know you do not need and it still works fine. I had tried to download only the updates I wanted but it won't do only those..it has to do every update for the last umpteen years unfortunately, but at least you can delete the unwanted ones.
Now that I have that figured out I am going to try and figure out using the baselines etc.
Hope this does what you need it to do.
