UBB.threads PHP Forum Software Community Forums UBB.threads 7 Installation and Upgrade Support Can't see the topics and replies

I've recently upgraded from 7.1.1 to 7.4 and everything seems to have gone correctly. But

I only see the "Quick Reply:" field when accessing a topic.

I see all the topics in the "Forum List" and am even able to post, but the view of the topic is empty. I am able to browse the topics with "Previous Topic" and "Next Topic" but they are all empty...

Anyone got any ideas?