I installed Xenforo and imported by Vbulletin 3.8.1 data over. It came across no problem.
My custom usergroup is set to allow people to edit their own posts. Timer is set to 15 minutes. People can edit new threads no problem but they can't edit old threads, from the Vbulletin side. I ran the analyzer on a person and then on the person/node. Both indicate that they can edit threads, yet they can't edit old threads for some reason.
This custom usergroup is the only usergroup they are part of.
FYI as a test I change the forum permissions from 'Inherit' for both the timer and edit own posts. That fixed it. I'm just wondering why. Why isn't it inheriting the proper permissions? I don't want to have to manually change all the permissions for each forum.