My Linux Mint volume vanished from the Clover boot menu after I updated to the latest version of Clover just ahead of installing macOS Sierra. This was the case before and after installing Sierra. No more Linux in boot menu. The actual volume is unchanged. The ubuntu folder is still present in EFI partition. Why no boot option?
I updated to Windows 8.1 and, of course, Macdrive no longer worked. In fact, Windows offered to 'repair' it, so I went along with that. As a result, Windows failed to boot. I reinstalled Windows 8 and re-updated to 8.1. Now I am wondering if BugsB's trick will work using the 8.1-compatible version of MacDrive's drivers with MacDrive 8. I haven't attempted it yet, but will let everyone know what happens when I do. Thanks BugsB for the tip. It worked great for the past year.