That 'reading' lang file error (while looking for a string) is a little bug in 1.0.6 beta 1, caused by some remaining reading stuff in the old logs. It only affects Recent Activity. Just logout and then login again and it will be gone. (I swear I will never change a module name again
)
The quiz error is new to me - did you upgrade directly from 1.0.5 to 1.0.6 beta 1?
Try editing your
database and doing this:
- drop all the tables starting with "quiz"
- edit "modules" and remove the quiz record
- visit the admin page as admin
...and see if it works this time.