Trying to add text but "Sorry, an abnormal condition..." pops.
My main purpose is to add subtitle into encore. After trying several srt converted to encore.txt format and nothing works, I resorted to manually type it in the subtitle track. Then this happens:

The 'title' cursor is basically red and don't allow me to click anything.
If anyone's thinking that 'there's no video, that's why it is not working', I've tried adding videos but it doesn't make any difference to this error.
What's going on?
Currently using CS5 Encore on MacOS 10.12.4.
