Marcus-
You can:

*!* Add a custom property to the form for the return value
oMyobject=CREATEOBJECT('myForm')
*!* In the myForm.Unload do this.hide instead of this.release()
oMyObject.Show(1)
*!* Check the return property in the form
lcReturnValue = oMyObject.ReturnValue 
oMyObject.Release()
IF lcReturnValue = "whatever"
  *!* et cetera.
ENDIF

You can either have the control bound to the form's custom property, or assign it in the unload().

>I know I can pass a parameter back to the calling form by using DO FORM myForm TO myVariable, but how do I accomplish this using a oMyobject=CREATEOBJECT('myForm') to instantiate?