Hi, I’m having this issue too.
I originally installed this plugin in September 2011 and it was all working fine.
Today I upgraded to the latest version of WordPress, and also BBPress, and now only admins can view the topics, everyone else gets the ‘Oh bother!’ alert.
I had an old backup of the old BBPress plugin so I replaced the new with the old, but no change.
The site I’m using is a staging site, ie it’s not ‘in use’, and I’ve not touched it or tested it since September, so I can’t be certain that the error is due to the WordPress upgrade…though as I mentioned nothing has happened on the site since then so it’s surely not a coincidence.
