Hi Mark,
the simplest solution is to do (in the case of say a number) an ActiveX step of SetValNumber of the class property object, passing in the reference to StationGlobals as the ActiveX ref, and "name" for the lookup string of the numeric you want to create (i.e. will create StationGlobals.name - and finally, the options setting, set this to a 1 (Insert if missing).
Of course you also need to give it a value.
This will update the StationGlobals, and if you look at the StationGlobals from the sequence editor, it will show a * in the title bar, indicating that it has changed (and needs saving)
Hope that helps
Sacha
// it takes almost no time to rate an answer