Never mind, found it. Thanks.
1) Unzip Dark N Dirty - 2.0 version.zip to C:\Cakewalk Content\Z3TA+ 2\Programs. To do this, right-click Dark N Dirty - 2.0 version.zip and select “Extract All”. You will be prompted to select a destination folder. You can copy and paste C:\Cakewalk Content\Z3TA+ 2\Programs into this field. You can also click [Browse]. In the “Select a destination” dialog click Computer and then navigate to C:\Cakewalk Content\Z3TA+ 2\Programs. When the location is correct, click [OK] and then click [Extract].
2) Open Z3TA+ 2 and select “Dark N Dirty” from the Bank menu at the top of the user interface. Choose a category, select a patch, and enjoy!