I have both downloaded on GOG when I launch London and hit install it tries to copy over the Fallout 4 then tells me cannot perform copy operation access is denied. I've run it as admin and tried reinstalling both not sure what the issue is if anyone knows a fix.

Navigate to your main Fallout 4 folder and find a file called CustomControlMap.txt. Right click on it, properties, then make sure you uncheck Read Only. I believe I had that problem first time around but it was a quick fix and it should install normally now.

This worked, thank you so much!

Just a heads up, I had the same issue, but my folder didn't have that specific file, reading the error carefully shows the path to the file that had the issue. Editing the properties of the file listed in the error fixed the issue.

One more thing I found with the same error, if the file is marked as "hidden" it also appeared to cause the access issue, after un-checking "hidden" the issue was resolved. In this particular case it was the ".ini" files in the "My Games" Fallout 4 folder (under "Documents")

Thank you so much my man. This worked perfectly.

YOU my guy are a life saver ty ty ty