$variables in Approvals for BuildMaster

I'm currently evaluating buildmaster as a build/release/deploy tool and so far I'm liking it a lot. I've found some minor cosmetic things that I'll submit bugs for soon however this is something that I hope I'm just missing something obvious.

I have a generic 'release' pipeline that moves packages from Alpha -> Beta -> RC and finally Release. I also have a deploy pipeline that deploys those packages and need to prevent deployment of packages in production that are only marked as alpha etc... The most obvious way I thought to do this is to have a Approval step that checks if appropriate release pipeline stage for $ApplicationName has been completed. However using $ApplicationName in my pipeline definition results in 'No application with the name $ApplicationName was found.'

Does $variable interpolation not work in this context? If not I think it really should as this was a fairly critical piece of the workflow I hoped to create. If it is a RTFM situation please point out where and you'll have my thanks.

Keep up the great work and thanks for building this tool.

Product: BuildMaster
Version: 5.7.3

Currently variables are not evaluated in pipelines. I'm not exactly sure on the pipelines/application setup you have, but you might be able to get away with using the Variable Value Promotion Requirement which forbids deployment past a certain stage if a Package Variable named IsReleased is not true. Combined with the Set-ReleaseVariable operation in the plan assigned to the release stage, you should be able achieve what you want, e.g.:

Set-ReleaseVariable(
   Variable: IsReleased,
   Value: true,
   Release: $ReleaseNumber,
   Package: $PackageNumber
);