Good question, manolito. The scenario is complicated by Win7/8/10.
If you run the batch file without elevation, then the command to copy the ocx into the system folder will fail and the regsvr32 registration process will fail as well.
If you run the batch file elevated (run as admin), then regsrv32 is executed, but the command prompt will start from %windir%\System32 and the copy command will not work because you lose the starting folder info.
In the mscomctl.ocx section of the readme.txt file I have inserted the note to manually copy the mscomctl.ocx file to %syswindir%, then to run the mscomctl_reg.bat file
Bye