Explicit action to add complex variable initialization in Assign

this could easily be solved with the addition of a button to the Assign Properties/Details tab which displays a variables selection dialog. The editor could then generate the appropriate XML to initialize complex variables. Apparently, the Riftsaw engine requires the structure of complex variables to be set before they can be accessed.

An alternative would be to add an "Initialize" tab to the Assign Properties, similar to the Variable Property sheet.