User Control problem when > 1 on same form

[batvink]

Hi,

I have created a user control which contains another user control (in same source). The inner control is a numeric text box. The outer control is a container for 3 numeric controls - X,Y and Z by default.

Here is my problem. When the control first loads, if you change the value in the Y or Z field, it actually appears in the X field. Once you type in the X field, you can do what you like in any of them and it works. I cannot for the life of me work out why this is!
I apologise for the rough coding, but it's been a while since I did any VB or object-oriented class stuff.

The control and source code is attached. I hope this is an obvious newbie mistake that someone can point out to me. Thanks in advance for any help.