OK, but how did you exlude the folder?
First, there are actually two exclusion lists: one in program settings, affecting the on-demand scanners, and another one in Standard Shield settings, affecting Standard Shield (i.e. on-access protection) only.
Second, it's necessary to put the complete mask to the exlucions, i.e. something like
c:\program files\perfect keylogger lite\*
or simply
*\bsdhooks.dll
I'd rather suggest the later, because of potential problems with long file names in the first case.