Hi !
You wrote :
"i succeded in making it accept any serial and making it fully functionally but the problem is when i restart it, it is again unregistered."

Yes, but to do so, you probably had to modify code itself.
So what about self-verifying code ? If your scr checks its own integrity (by generating a checksum for example) or in another way, it could decide to reset password validity each time. Try looking for any memory read access in a short range near your modification using BPM xxxxxxxx R in SI.
If SI popups, then, you're in the checksum routine.

Another possibility for this proggy is to use multiple serial check routines. At startup, if it randomly use one that you've not changed yet....


So, there is too many possibilities... I suggest you to reverse the serial check routine in order to find a working serial or making a keygen instead of patching.

Hope this could help.
bye.