After installing CTM 2.9 not work commands like ping

Bug Reports - CTM
1

After installing CTM 2.9 not work commands like ping (from c:\windows\system32).
Before installing they works (I often use this command).

Environment variable %PATH% =
"C:\Program Files\COMODO\Time Machine;C:\Program Files\Nmap;C:\Program Files\Common Files\Ahead\Lib"

That is, %PATH% contaned not only “C:\Program Files\COMODO\Time Machine”.
That is, %PATH% not replaced.

I run command set PATH=c:\windows\system32;%PATH%
and all rights - ping is work.

What happened?

Thanks.