It was actually a conversion from html that caused the problem... normally I would run an epub through calibre to reset the font and strip out the css font information but for some reason I didn't do it with this file... it loaded ok in SIGIL which reported no problems.. it's no biggy just thought I would advise t1 owners in case they had the same problem it's just that file handling is pretty basic and it should be handled better on the t1
