The following seems to work in the 2010 version, so I am hoping it will work for the Mac 2011 version.
1) Add a named range, I called it 'Priority', with the following formula as the 'Refers to:':
Formula: copy to clipboard 
=INDIRECT("TASKS!$f$12:$f$"&COUNTA(TASKS!$B$12:$B$1001)+11)

2) Set the 'Applies to:' of the conditional formatting rules to: =Priority
Note: As soon as you hit the 'Apply' key the 'Applies to:' will change to: =$F$12:$F$43 so it will appear the process didn't work.
3) Add a row inside the table and look at the conditional formatting rules again and they will now be applied to =$F$12:$F$44 and if you remove a row they will again read =$F$12:$F$43
Let us know if you have any questions.