Perforce Create Changelist does not set the FB variable

FB 7.0.0.2610
Host: WIndows 7 SP1
Perforce: 2012.1

I created variable ‘BuildChangeList’ in Variables\Project. I’ve tried types Variant, Integer and String all with the same result.
Format string is empty
Default value is zero
All check boxes are unchecked.

I used this variable in the first step: Perforce create Changelist:
- Select ‘Create new changelist’
- Set FB variable: ‘%BuildChangeList%’
Changelist files and Jobs are empty.

Running the script, set a breakpoint on the second step I use a watch to check the variable value and it’s zero despite the log reporting that a changelist has been created.

Project file attached

In the create changelist action, in the variable field do not use %, just select a variable from the drop down list.

Sorted, thanks.

David