You might be better off posting this question at style_system or dw_styles, as it is a style specific question. But, as far as I know, there is only free text box for each layout - I don't know if there is a max amount of text you can put in it though.

Again - you might get a better response at either style_system or dw_styles. The people developing the style system, including the new Core2 Tabula Rasa, are more likely to see your question there.