When I clicked on Dolphon's address bar it changed to: "mtp:Nexus 10/", but didn't get anything. I changed it to what Thunar had "mtp://[usb:004,003]/", but that doesn't work. Thunar in MX-KDE doesn't see the tablet at all.
I think you left out the "/" between "mtp:" and "Nexus 10/", i.e., it should be "mtp:/
Nexus 10/". Are you sure you entered the right path?
1) I discovered that I don't have to use Device Notifier to open my Kindle; I can open Dolphin and navigate to it by typing in "mtp:/Kindle/" in the address bar. But it has to be entered exactly that way -- no "/" before the "mtp".
2) I discovered I can also enter this terminal command: dolphin mtp:/Kindle
3) This trick doesn't work with Thunar running in KDE -- only Dolphin.
I was hoping that if we could get 2) above to work on your system, all you would need to do is change the Device Notifier command to something like this: dolphin mtp:/Nexus 10
However, I'm beginning to think that mtp just does not work on your system for some reason. This is very puzzling, because all the right pieces are in place on your system as far as I can tell.
One final thought: What version of Dolphin are you using? Mine says it's "Version 2.0 Using KDE Development Platform 4.8.4"
I also found out the Kindle works with Konqueror as well by entering this terminal command:
You might want to try that too.