Is there a list of the CAN states anywhere? I did not see anything in the instructions.

Sure, all the elements after dot in a channels list in the Client are what you are looking for:
There is also CANbus State panel:
Does the state value change based on any of the errors?
Correct, canN.state is a bitfield. Displaying it in the Graph Log shows a graphical representation of all of the bits in a neat format.
Sure, take a look at the screenshot below. This is a bitfield that carries information about specific errors on each bit.