Same thing, launcher closes after hitting play. (Before d/ling the patch I got the Unspecified error but restarting the launcher fixed that)
1. Tried deleting Bitraider folder, no go.
2. I don't seem to have a client_settings.ini file anywhere.
3. Tried deleting swtor.exe -> got unspecified error again, restarted the launcher, this time got "unable to retrieve patch data, please check network connection", restarted again, got to the point where I can press play... launcher closes, nothing happens. I checked the install folder afterwards and the launcher apparently hadn't re-created the .exe file either.
Now I just got unspecified error again. Starting to regret signing up for that security key (and yeah, I even tried failing to input it but it didn't work either).
Meanwhile, flatmate has been happily playing in the next room.