The hot patch nops are the first place any decent anti hack software looks, I am sure Hack shield would scan there if they are scanning the functions entry point. there is 6 bytes allocated just before the entry of the function these are normally nops 0x90 then on the function export table it will be the original address - 6 bytes, when this function is called with the new address there is normally a patch which jumps to another function, it goes something like that... it was years ago I played with microsoft hot patch area because its normally the first thing checked in any good hack detection software