Core Version Items Collection has no Button to Click on

Hi

I have Tested the two Versions in the ZIP File

The Dot Net Framework Works
Ribon Control

Click on Tabs Collection Button

Click on Panels Collection Button
Click on Items Collection Button

The Core Version Will Not Work.
Ribon Control

Click on Tabs Collection Button

Click on Panels Collection Button
Click on Items Collection There is not Button

Thanks
Tom

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