>>>>Thanks a lot in advance,
>>>_
>>>I think you have to select the column prior to adding it.
>>
>>Do you think I'm THAT stupid? :)
>>
>>I select the column (Grid, Edit, select the column) then try to drag and drop from the project.
>
>Not with Drag & Drop.
>Just click on Button in Controls Toolbar and then Click in Column.

I wanted to add a button of my own class. But let me try with the regular button now, may be drag and drop was my problem.