Dvd Flick - How To Enable Html Tags In Subtitles?

Hello there. I am making own DVD images to be burned later (mainly movies), some with downloaded or self-made subtitles. Some of them contain simple HTML tags (italics), which are supposed to be eighter lyrics of a song or a story telling. But when ISO image compiled with DVD Flick, these italics subtitles are without formatting (displaying as normal straight subtitles). How can I enable italics for my subtitles without affecting all subtitles (I don't want to have all subtitles italics, just where I used the italics HTML tag)?