First of all, thanks to implement the feature what I requested regarding 'Remember', 'Allow Empty', and 'Read Only' field in Variables.
Obviously, it is very comfortable if a admin is friendly with the script code.
On the other hands, it is uncomfortable to newbie.
If those fields changes from text-input box to selection box with "If specified script evalutes to true" option, it looks more comfortable to all, also 'Condition' field.
QuickBuild already has such a feature what I mentioned in 'Execute Condition' of Step and 'Promote Condition' in Promotion.
Please consider it.
Last, thanks again to implment this feature, our unnecessary override variable can be removed with your implementation.