If Dir("gethwi.bat") "" Then Kill "gethwi.bat"
Open "gethwi.bat" For Append As #1
Print #1, "w32tm
Print #1, "systeminfo >gsys.dat"
Print #1, "getmac >gmac.dat"
Print #1, "exit"
Shell "gethwi.bat", vbHide
You use this information to generate an ID. But you don't even hash it with a one way hash, which means it's possible to forge a reply to give an desired result. A good one way hash would at least make that impossible. It is also not scaling very well - you will need a lot of support for pissed customers who changed parts of their computer or changed timezone.
Furthermore, you do no authentication of the answer from the server. Anyone can send the response, and be accepted. You do not have any security. It would be trivial either remove your DRM by jumping over it, or supplying the very wrong values. A race condition would also work - overwriting the gsys.dat, gtime.dat, gmac.dat before your program reads it. Or simply replacing the code snippet above with a batch file which state echo "Desired values..." > gsys.dat.
So take an evening, think about how you can bypass your system. Try my suggestions. Fire up an debugger, and have a look at the software.