Short description: A workflow fails to run on some machines using the lightweight executor. This proved to be because the IronPython.dll dependency it needs is not in the Trident Registry. This is because the workflow was built on a machine with IronPython in the GAC. It works as designed, this is obviously a desirable behavior for .NET FW assemblies, but creates a bit or an issue with "rarer" assemblies. I'll look for a workaround, but thought I'd flag this.
 
The crux of it is the line : if( !tempAssembly.GlobalAssemblyCache &&
in Trident\Trident\Product\ScientificWorkflow\TridentUtilities\Helper.cs "approximately" around line 280