Under Tables > Stack, the option for "multiple series stack" is very helpful in some data situations. Would it be possible when "multiple series stack" is selected to have a preview box to show where the columns would go for the two options: (1) every nth column vs (2) n columns in a row (contiguous)?
If Number of Series is used, preview panel box would show which columns would go in 2, 3, ... n groups, or highlight the first of the series in the upper column dialog. So if 3 was entered, the 1st, 4th, 7th, etc column selected would be highlighted above to safe space.
If Contiguous is checked, would show which columns in how many groups of contiguous columns are being stacked.