There are multiple widths that you must take into account when modifying the report definition manually. For example, the Crosstab width should be equal to the combined width of its columns, which is not the case in the provided screenshot
Our suggestion is to modify the column widths via the report designer and then review the automatically generated TRDX file. In this case you will be able to see which properties you need to change manually in order to achieve the same effect.
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