That's a feature, not a bug. KitKat 4.4.2 severely limits how apps handle the removable sdcard as a "security measure."
Some apps can read/write to their own space, but generic file explorers can't manipulate the files (rename, delete, etc.) With root, there is that ability restored, but not the ability to move to sdcard.
On the other hand, the device appears to use the entire 16g/32g internal card for apps, bypassing the 2g ROMspace limitations. I haven't double checked that.