I am using VFP7 SP1.

I have created a form that runs fine from the command window or programatically. I then saved the form as a class to a class library.
I call the form thus:

SET CLASSLIB TO myCLASSLIB
oLoc = CREATEOBJECT('locscreen')
oLoc.Show()

I IMMEDIATELY get this error when program execution hits the oLoc line:
"Expression evaluated to an illegal value (Error 46)
An expression specified by SET MEMOWIDTH, BROWSE, or an @ ... TO command evaluated to an illegal value."

The error fires before 'locscreen' is even visible.
I can find no way to Trace or Debug this error.
I have reviewed all methods and properties. I have reviewed my variables.

How can I trace WHICH Expression is evaluating to an illegal value?

Thanks.