If you're having problems installing: Please use this link: https://workspace.google.com/u/0/marketplace/app/sciwheel/800143025315
Alternatively, you can go to Google Docs and select Extensions > Add-ons > Get add-ons. When you search for Sciwheel you'll see 2 listings, please choose the one on the right hand side (with the least amount of downloads):
This is the latest version and will work as expected.