Merging cells results in blank rows.

[hexin-666]

Number of merges * Number of dynamically generated rows = Number of blank rows。

It doesn't take effect.

[luca-vercelli]

Trying to understand this problem, I realized it has nothing to do with mergeCells.
Problem arise whenever you have 2 commands on the same line, and a third command below. Third command is shown after some blank lines. Here is a test case.

Issue321Test.xlsx

[luca-vercelli]

I suspect this is the same bug reported in #62 and #296