Can you help me on a few things I want to implement in my ActiveX TextBox?

How do I populate the my TextBox DataField, DataMember and DataSource properties which I have implemented? Also, how I would go about creating an ellipsis and how do I implement the Drop Down Box on these Data properties as a normal Text Box would be. I've built a Properties page but cannot for the life of me find anyway knowing what controls are active on my

Your help would be much appreciated
Kieran