Hmm, this is working just fine for me, I can increase or decrease the width of Columns as I please. I can either click hover the cursor over the vertical cell border marker line on the ruler above the generated schedule, click and drag it to adjust its width.
Or I can simply double-click that vertical marker line and the width of the column will adjust to the smallest width so that the text and 2D/3D Views still fit.
Alternately, there is a ... button at the upper left corner of the schedule, where the vertical and horizontal rulers meet. Click it and it takes you to a Dialog where you can manually specify the width for Columns and height for Rows.
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