When clicking on mark this forum read on Wrestling with Demons, it moves on to Eternal Conflict, but it has the old layout of Eternal Conflict. The blue one.

Thanks a million, trying to replicate this bug and I can see it is happening, looking into it and hope to have a solution as soon as possible.

Ok, I found the cause of the issue. When you 'Mark forum as Read' it brings you to the category in which that forum is in, which is the same category that houses EC and has the EC scheme applied. I have removed the scheme from this category to avoid confusion in the future.