Hello,
I've come across this bug and it always happen in specific circumstances. I believe it is specific to Windows 10.
Steps to reproduce:
1) Enter password / accept EULA everytime (gosh darnit) / press Play, you must be in borderless window mode
2) Right after pressing play, focus on another window
3) Once you can see the character login screen, click Play on the character you want to play with the first click, as in don't click in the middle of the SWTOR window then Play, right away Play.
A video of it happening
Here's my DXdiag
