I'm using WiX installer and WixUI_FeatureTree UI. I want to customize the Welcome Dialog window by adding one more text control. How can I do that? I search the documentation and didn't find anything
I that is not possible then can I change the height of the "Description" control? I tried like this but the Height was not changed?
<UI>
<Publish Dialog="WelcomeDlg" Control="Description" Property="Height" Value="150"></Publish>
</UI>
Adding a new control would require replacing the entire dialog and re-wiring the UI sequences to get your dialog to show up instead. You can read about that here: Customizing Built-in WixUI Dialog Sets.
If you just want to extend the contents of a control, WiX v3.6 has a new feature that allows .wxl files to not only change the text of a control but to change it's coordinates as well. Bob Arnson has a good article on that here: Localizing more than strings in WiX v3.6.