Ubuntu-sdk emulator does not work

I'm trying to lea how to make scopes using the ubuntu-sdk. However, I can't make the emulator work properly, so I can test my work. When I run the scope, theSDK launches an emulator, which will then be stuck in booting. It does not get ready,and th esdk says it's waiting for the device to get ready.
I can't use the + under devices to add a new device, as the documentation otherwise says I should do, so I had to add a device using the terminal. When I try to test a device under tools->options->device I get an error:
Coecting to host...

SSH coection failure: Coection refused

Device test failed.

I can't change the ports or anything.
It has taken me forever to get thus far, and it has been rather frustrating to do so - so any help would be greatly appreciated. Thank you