Calibre to Libra Colour comic issue

Hi there, im relatively new to using calibre and also kobo devices, transferred a few books and stuff using calibre and have the koboutilities plugin with the extended drivers.
There are a few comics im trying to transfer however that are not resizing to the correct size, being too large for the devices screen and not being able to correct it. Is there a way i can correct this in calibre for the libra colour and if so can I be pointed in the right direction? Thanks :)