Hi,
Recently i was able to successfully crack a software ( My first independently cracked software). However when i patched it and ran it, it crashes. So there is probably a CRC check somewhere. So i thought of writing a loader. Went through lot of tutorials but was confused.

I need this

00444272 74 5A JE SHORT GJX2000.004442CE
00444274 . 837D A4 01 CMP DWORD PTR SS:[EBP-5C],1
00444278 74 0F JE SHORT GJX2000.00444289
0044427A . 837D A4 45 CMP DWORD PTR SS:[EBP-5C],45
0044427E 0F84 87000000 JE GJX2000.0044430B
00444284 E9 BC000000 JMP GJX2000.00444345

to be this

00444272 75 5A JNZ SHORT GJX2000.004442CE
00444274 . 837D A4 01 CMP DWORD PTR SS:[EBP-5C],1
00444278 75 0F JNZ SHORT GJX2000.00444289
0044427A . 837D A4 45 CMP DWORD PTR SS:[EBP-5C],45
0044427E E8 71330600 CALL GJX2000.004A75F4 ; JMP to mfc42.#2818
00444283 90 NOP
00444284 E9 BC000000 JMP GJX2000.00444345

Is there a simple tutorial out there to work with DUP or any other software for making loaders??

see the following tutorials
http://www.netyi.net/blog/user1/4433/archives/2005/4227.shtml#6634
http://bbs.pediy.com/showthread.php?s=&threadid=13951

If it crashes, it's not a "successful" crack.

Why don't you look for the CRC check and NOP that out? I see that as a far simpler solution than trying to write a loader for it.

Completed,
It was the damned CRC Check. USed Abel Loader to make a loader. Works like a charm. Guess now i can now crack and also make a patch so that makes me a full fledged cracker ?? Sort of .
Thank you everyone