Hey drdon - a quick fix for this is to first copy and paste your text into a basic text editor - like note pad etc - then copy and paste it into unbounce - should fix most of your problems. then you can choose your line height

I also recommend copying the text in the SOURCE view. This way any formatting from where you copied it gone.

Then to double space exit source view by clicking on the button again, select all your text and use line height for spacing.