Cannot answer to those.
The Windows way to deal with "Fixed"/"Removable" has been historically a PITA and the use of a filter driver (or of a reversed one) have been historical "workarounds" to the stupid way windows was dealing with the devices.
It is poossible that Windows 10 has ONE, SINGLE thing "right" in this new version, and very likely (as Akeo and Steve6375 noted):
this will create havoc with Linux/Android sticks, the "common user" will be overwhelmed by any number of added drive letters.
About the IFS driver(s), it is possible both that:
1) the issue is not in them but in the USB3/multiple partition combo
2) the issue is in the actual way the driver is installed (or improperly installed, missing a dependency, etc.)
It is easy to test this with either a real partition/volume on an internal disk or more simply using any virtual disk, even IMDISK will do, just mount with it a small EXT2/3/4 volume and see if the filesystem is recognized.