I haven't been able to recover my forum since this last upgrade. Of course the upgrade by itself probably would not be much of a problem, but I took the opportunity to try implementing a few other changes, and haven't been able to recover since. The story goes kind of like this...
1. remove old phpbb files
2. export database (except the few Garvey's tutorial said not to)
3. delete old database
4. create new database with a more generic name
5. install latest phpbb (in a different directory... why I did this I'll never know

)
6. remove from database tables previously exported
7. import saved table data
8. forum doesn't work... there seem to be three contributing problems..
a. changed directory
b. second theme apart from subsilver
c. mod to allow users to select theme of choice
.
.
.
.
1,000,000. Have tried a million different things.
Seems like it should be an easy fix. Sometimes things look promising, and then everything falls apart.
/me begins to wonder if I should try porting over to SMF... but wonder if I can do that without a working forum in phpbb.../