OK, leave the 1lp and more than 1 lp rules the same.
change the 1 cd rule to:
Name: 1 CD:
Triggers:
Number of items where 'category' has a value of 'cd' is '>=' a value of '1'
AND
Number of items where 'category' has a value of 'lp' is '<' a value of '1'
Calculation:
Flat Rate: 8.99
and change the more than 1 cd rule to:
Name: More than 1 CD
Triggers:
Number of items where 'category' has a value of 'cd' is '>=' a value of '1'
Calculation:
Flat Rate:
($this->ConditionalTotal("Quantity", "category", "cd")-1) * 4.50 + (($this->ConditionalTotal("Quantity", "category", "lp") >=1)?4.50:0)