David,

 

I can't reproduce your problem by using HorizontalAlign=Center ,

 

I think if you using ASP.NET 2.0 THEME,

 

Not only the .skin file, but also the css files in the THEME folder, can affect the editor dialogs.

 

So I think you can try this way ,  specify another theme in the /CuteSoft_Client/CuteEditor/web.config and try again,

 

Regards,

Terry