3D Watch/Model continually flashing

Hi

I’m new to Dynamo (and Revit). Starting with something basic, I’ve figured out how to read values from an excel file to create geometries and how to combine the resulting objects into a single solid.

I’ve added a 3D Watch as my final node. I’m having an issue with the display within the 3D watch window continually flashing/blinking and I also have the preview of the model flashing in the background behind the code/nodes. This happens irrespective of whether I have run set to auto or manual. It starts happening as soon as I re-size the 3D watch window.

Has anyone else experienced this, perhaps I’m doing something obvious wrong (other than re-sizing the window…)?

See my code below, the 3D watch window is blank due to the screen grab being taken during an ‘off’ flash, but when it does display the model looks as expected.

Any tips appreciated.