Conditional Build Rule Bug
 

This looks like a 6.3 bug to me. If you have a conditional build rule that is not an 'is true' condition and you do the following:

1. Open the Step
2. Select 'Always build this step and child steps when checked'
3. Click 'OK'
4. Re-open the Step

The Conditional Build Rule drop down box displays 'is true'.

It is working as designed. The radio buttons 'Always build/build only' and the 'is true/is false/etc.' combo are both derived from the same underlying value, so if you set it to Always build, the previous combo selection is no longer stored/available (and it doesn't apply/is disabled when set to 'Always build').