Apologies Rod for not anwering your question! I do have Scaleable HTML content checked and yes the content gets larger if I make the LMS window larger.

I changed to the above after reading some threads and it didnt resolve. I originally had it on High.
Thanks so much
Turn off Advanced Project Compression. That particular setting is the MOST likely reason you have ghost lines in your content. (I would have thought this would have been suggested in those other threads you said you had seen.) If that resolves the issue, you may be able to turn on some of the other compression settings.
I would also suggest you turn OFF Scalable HTML. Captivate content will look at its best when it is NOT being scaled.