Hello,
I made XLSX template containing formula SUBTOTAL for sum area A3:A4.

If I open this template by XLSRW 6.00.59 and try to write "X" to the cell B3, I get the error "Empty stack" with resutt code 10 .
If I open this template by XLSRW 5.20.71 and try to write "X" to the cell B3, I get the error "Empty stack" with resutt code 10, too.
(If I try the same with template of XLS version by XLSRW 4.00.65 everything is ok.)
The template is at http://www.genet.cz/kohout/xlsrw/201910 ... mplate.zip to download. (link for example corrected 20191218)
Josef Kohout