The properties define outermost columns that are not replicated when this sub-rule is applied.
property SkipLeftColCount: Integer;
property SkipRightColCount: Integer;
When this sub-rule is applied, its rows are replicated. However, cells in outermost columns may be not replicated but merged across all replicated rows.
SkipLeftColCount defines the number of such columns from the left side (withing columns of the parent rule).
SkipRightColCount defines the number of such columns from the right side (withing columns of the parent rule).
So, FirstRow and RowCount define the range of rows which will be replicated, SkipLeftColCount and SkipRightColCount define replicated and not-replicated columns.
However, there is a difference. All rows of the parent rule outside the range defined by this sub-rule's FirstRow and RowCount do not belong to this sub-rule (they may belong to another sub-rule, or not). All columns of the parent rule outside the range defined by SkipLeftColCount and SkipRightColCount are still considered as belonging to this rule, and they are processed immediately after processing the replicated part of this sub-rule.
When this sub-rule is applied, all cells belonging to these outermost columns are merged vertically (see the "Example 2" in the topic about SubRules). If MergeWithPrevious = True, all cells belonging to these outermost columns are merged with cells of the previous sub-rule, if the following conditions are satisfied:
•this is not the first sub-rule,
•rows of this sub-rule are located immediately below the previous sub-rule,
•the previous sub-rule has equal values of SkipLeftColCount (cells of the leftmost columns are merged) and/or SkipRightColCount (cells of the rightmost columns are merged)