Can you explain the behaviour you want?

ComboBoxes are typically used by the user clicking in them, not by typing text in a random order and seeing the list reset its contents then using enter or arrow keys to type more numbers.

Edit: I've just had a look at the working Excel code that you referred to in your first post. I'm not seeing any value in stepping away from the actual code shown there. Why have you varied so much of the code in your implementation?

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Andrew Lockton
Chrysalis Design, Melbourne Australia