Yepp, completly correct. Did you receive the release email where I wrote:
Please read the manual concerning normal mapping.
Until I forgot to add the correct version of the pdf, there should be an description of the procedure. To be as maya compatible as possible, I use the bump2d node with one exception: I added a normalMap attribute to the bump2d node because the built-in procedure is quite error prone. So you simply load your normal map, connect it as bump map to the Corona shader and connect the normal map to the normal map attribute on the bump2d node. This should work.
bump mapping is not supported yet.
Concerning maya materials: The question is if it is necessary to support them because they can only use a subset of the corona material and a lot of paramers cannot be translated in a sophisitaced way. If you want to do anything interesting, you will have to use the Corona material anyway.
You are correct, per face materials are not yet supported. A wish list would be really great. I'd collect the ideas and start a poll.