If you have a laptop with a touchscreen (as the newer Walden laptops do), you are unable to use the drop-down menus in the LibGuides backend. This is due to the way the browser interacts with the touchscreen. Springshare kindly sent us the workaround for this issue.
Reordering boxes should work now, though it can turn touchscreen support off altogether for Chrome or Firefox.
When you're done editing your guides, you can either leave this setting disabled or use the same process to re-enable touchscreen support.
Hopefully, Firefox and/or Chrome folks will be able to fix that bug sooner rather than later, but in the meantime, at least you now know how to work around it.