It is my understanding that both Active X ListBox and ComboBox commands are able to be interfaced with Peter'a code, but I am having this confirmed!

There's also code availble,provided by Jaafar Tribak and posted in a forum titled "Re: How to get handle to a control on a spreadsheet? ", which does allow a mouse scroll interface with ActiveX listBoxs controls.
This code does appear to be based on Peters, but as I havn't been unable to make contatc with Jaafar to discuss His code, I a still waiting for clarification on combobox mouse scrolling.

However, I am doing my best to push forward some clarification son Peter's code and to hopefully post back some working examples