Hi Jeff;
My general advice is "Never ever and if in doubt never, use the Constructor event to initialize a control"! The reason why is that newer versions of the MS-Windows O/S and/or PowerBuilder can often change the timing and internal process order of operations during the instantiation phase of a class.
To circumvent this, always create a PostContructor user event on any given control class and then use only the UE for initialization purposes. This gets even more critical when you move to other O/S's like Citrix or iOS/Android for example with Appeon.
All by frameworks use the PostConstructor and have been since v1.0 - circa 1993/1994. This technique has really saved my *** over the years and PB/OS releases. I still have PB 2./3 code that migrates "as is" and runs perfectly under PB v12.6 using this approach.
Food for thought. 
Regards ... Chris.