On the install - I tried it using both VMware and the MSFT equivalent. It seemed to be trying to get to the physical MAC and knowing when it wasn't. I'll give virtualbox a go.

Re the manuals - No I would say not. It's a set of very terse descriptions for the Mercedes trained mechanics. The paper workshop manuals I've subsequently obtained (for Vario, not Unimog) are similar. Lots of pictures but almost no text. I'm not aware

There are some Unimog websites which do have good "How to" sections on them. That might be a better starting point.