If you are stuck in eShop Test mode and cannot find the Screen Options tab so you can get to 2 Column mode, try this:
1. Create a *new* WordPress Admin user for your site, then log out, clear your browser’s cache, and log in as the new user.
2. Go to Settings > eShop and click Screen Options at the top-right corner of the screen under “Howdy…”.
3. Click “2” for Number of Columns.
4. You should now see eShop Status on the right side of the screen, where you can change “Testing” to “Live”.
5. Click Save Changes.
eShop should now be in Live mode, and you can now log out, log back in with your regular user name, and delete the new Admin user you set up in Step 1.
This worked for me. The key to the whole thing was setting up a new Admin user as described in Step 1.
Hope this helps.