OK, I've just updated phpBB (the entire board's framework) from 3.0.2 to 3.0.3.. there were some issues with the country flags mod, which broke the ability to view topics. This was resolved by downloading the full package and using the new version's view_topic.php, since it appears the core functions to the country flags addon were lost in the merge. I won't be missing it, but you watch, I bet it starts to annoy me and I add a new flags mod.
Let me know if you experience any problems - the sooner I spot them, the better - and given this one included updated default style pages, and we're on a modded style, it may need some more 'hands on' updating of the actual template pages.. hopefully not.
It was getting stuck on the last file, too, which was resulting in it not completing the update and reporting the same (directly copied) file was not updated... I worked around this by directly updating the "check for updates" tab of the admin control panel to report the new version.. this wasn't really a lie though, since the general tab was correctly reporting the updated version already, and it was on the final file of the update, which I copied in manually.
The phpbb.com forums has a few people reporting the same difficulties, but no solution has been offered.. I just posted what I did, but it seems that's a moderated forum, so it'll be interesting to see if they let my 'hacky' solution through.