You need to tell the edit box when it should get focus. The following should be the normal behaviour of an edit box.
Code:
<OnMouseDown>
self:TakeFocus()
</OnMouseDown>
<OnEnter>
self:LoseFocus()
</OnEnter>
<OnEscape>
self:LoseFocus()
</OnEscape>
I don't think the text attribute works and most of the others should be the default values.