Kindle comic converter

Recently I’ve started using kindle comic converter (when I need to) and the files from there work great on the kindle when in mobi format but not so great when I’m awz3 format. Yet comics and manage I’ve bought and downloaded then saved and uploaded through Amazon and calibre (buy or borrow book, download and upload to calibre then save to sd card) work fine in awz3 format. For example when I’ve downloaded from the internet and had to use kindle comic converter I’m only able to view full screen and pinch to zoom in mobi format. I’m awz3 format the books converted with kindle comic converter don’t show up full screen and when I try to pinch zoom it only show up on screen in a little box that mentions font size. I’m sorry if this is confusing but I really appreciate anyone who’s able to shed any light on this.