Hazel not retrieving from Trash

Hello,
On my previous hard disk, Hazel was set up to retrieve any iOS apps found in the trash and move them to an "Old iOS apps" folder in my documents folder (to keep automatically an old version of apps in case updates proved unsuitable). She did the job splendidly (and still does when I boot into the old disk).
On my new hard disk, I made exactly the same folder in Documents. I exported the rule from Hazel on the old disk and imported it to the new. However, Hazel will not retrieve .ipa files from the Trash and cannot even see them using "preview rules". I have set Finder to show all extensions.
Both the old and new hard drives are using the latest Mountain Lion.
What am I doing wrong?
On my previous hard disk, Hazel was set up to retrieve any iOS apps found in the trash and move them to an "Old iOS apps" folder in my documents folder (to keep automatically an old version of apps in case updates proved unsuitable). She did the job splendidly (and still does when I boot into the old disk).
On my new hard disk, I made exactly the same folder in Documents. I exported the rule from Hazel on the old disk and imported it to the new. However, Hazel will not retrieve .ipa files from the Trash and cannot even see them using "preview rules". I have set Finder to show all extensions.
Both the old and new hard drives are using the latest Mountain Lion.
What am I doing wrong?