If you copied files over they may have been marked read only. You need to give them read/wrirte. Not sure how to do it for a whole nested directory but I'm sure if you check on the internet the instructions can be found.
I think it's better but ran the beta for it so I was used to it. It does take a little while to get used to the differences.
Glad you sorted out your issue, may have happened on an update. Like anything time fixes a lot of things.