Then it's not related to my app. To be quite frank, there was nothing in your log that pointed to my app. I just ran the tool. Your error points to Forums app template, not Tutorials app template. To make sure, go to Applications and disable Tutorials and go to any topic. If the error is still there, it isn't coming from my app.
Then run the IPS4 tool in your ACP -> System tab -> Support -> Something isn't working correctly.
If still insists, open a ticket in Client Area.