I'ev had that happen, it is a known issue that may or may not have been resolved. I don't know for certain since I haven't checked the bug tracker for a day or two.
There are two fixes for this that I am aware of: make a new character, or ask for DM assistance in moving to a new location which will clear the bug. You won't be able to see what you're typing or what anyone responds with, so you'll have to be specific in your message. When you get to the black screen, don't click on anything and don't hit any buttons except the following:
Press Enter to move the cursor to the message bar. Then type:
/dm Stuck at black screen, can't see responses. Please help me move to <location>
Just enter in your required destination instead of <location>. If it is a new character, then you will need to go to the rift. Once you've typed the message, perss enter to send it and hope that the gods are awake
