Duplicates CTD Greentop during upgrades....

[Nunya]

I had about 12 upgrades needing attention, so I went around one-by-one hitting upgrade. I didn't wait for each one, just daisychained them. I'm wondering if the sheer volume of upgrades at one time was too much for it!

 

[OwenHo]

This could be an issue, specifically on a lower end machine. The latest patches try to resolve this by staggering upgrades. You will need to stay in the settlement while the upgrades take place, depending on you computer 5 or so minutes. So take a break, pet the dog, hug the spouse, move around... you get the idea.
Thank you