Remove the Zotero add-on to Firefox
Open Firefox, type about:addons into the location bar, and click on the Remove button for the Zotero add-on. If you see two Zotero-related add-ons (i.e., Zotero and the Zotero Word for Mac plugin), you need to remove them both.
Clean up your old Zotero-in-Firefox data
This part is harder. Open a Finder window by clicking on the smiley-faced icon on far left of the dock at the bottom of your screen. Make sure you’re in your home directory by clicking on the house icon. Type ⌘-J to pop up the View Options menu. Check Show Library Folder at the bottom of the menu. Open the Library folder. Inside the Library folder, open the Applications Support folder. Inside the Applications Support folder, open the Firefox folder. Inside the Firefox folder open the Profiles folder.
Once you’re inside the Profiles folder, you should see exactly one folder, with a name made up from some random letters and numbers. Mine, for example, is p572h74i.default. The exact alphanumeric string will be different for each of your profiles, but that gives you the general idea. Open that folder, and inside you should find a zotero folder. Delete it by dragging it to Trash.
Install Zotero Standalone
Go to https://www.zotero.org/download/, and follow the instruction in the blue box on the right (“Download Zotero for Mac”, and “Next, add one of the following browser extensions”, making sure to choose Firefox, which should be highlighted).
Install Paper Machines
Go to http://papermachines.org/install/, and follow the instructions for installing Paper Machines in Zotero Standalone (i.e., “To install in Zotero Standalone, right-click (control-click) the link above …”)
Run Paper Machines
You should then be able to right click on the Assignment 7 folder in the English 294 Group Library and get word cloud and topic modeling results.