[QUOTE=tshering;2128754]I guess you are saying that one cannot possibly reference fonts outside of the container. Right? The possibility to reference to resources outside of the container would be convenient in several respects, e.g., cross references between several epubs. Is there any means by design or hack to make this kind of references possible?/QUOTE]
Nope, I was just referring to taming's question about whether you wanted it to work even without the right fonts installed, and quoted your statement that the books were for people who already have the fonts.
You might be able to reference fonts outside the container by using CSS or HTML. Say something like font-family: Name1,"Other Font",More; in your CSS stylesheet. Just do it like using a stardard font like Georgia on the web; the @font-face might be confusing the device.
Referencing fonts in other ePubs would be a bad idea, and I'm pretty sure that it's impossible anyway.
PS: Have you tried installing Unifont on your Kobo to at least test it?
The issue with automatic loading might just be a problem with your test fonts.