It's been my understanding that when using Test Lab in Quality Center, if changes are made within a script, i.e data/ criteria change those updates DO NOT go backwards and update the the case in Test Plan.
Is this correct?
In version 10 of Quality Center at least modifying input or expected results makes QC to ask whether you want to update the test case in Test plan. I'm not actually sure if this is the case with scripts, but I would be suprised if not.
If you answer affirmative, the test case will be checked out for you and changes are updated there. You then need to check in the changes (or discard them).