Well, I created a simple package by going via SSMS and doing Export Data, then just saving the dtsx package. It is simple select statement with one column only from one table to export to already existing (but empty) excel file.

It creates the Program.cs output file, but it is empty... the cmd screen says when I try to run this

c:\SSIS>csharp-dessist.exe --ssis_filename=c:\ssis\pckg2008.dtsx --output_folder

=c:\ssis

SYNTAX ERROR:

Method '--ssis_filename=c:\ssis\pckg2008.dtsx' is not recognized.

I've attached a zip file with my examples.. I tried few other packages, but to the same avail.