Does the Morgana FSN number?

Yes it does.

Does the Morgana FSN number vertically and horizontally?

It depends on the numbering head that you connect to the machine, you can have standard heads or convex heads (vertical length number). You can also have forwards counting heads and backwards counting heads; and numbering heads that are not just numbers, but letters as well.

Can I add more than one numbering head?

You can add up to 8 on each wheel of the FSN, the FSN comes with 2 wheels, but could technically be upgraded to a 4 wheel system.

How many perforation and scoring wheels can the FSN take?

It can take 5.

What is the difference between the FRN and the FSN?

FRN is a friction fed machine, the FSN is a suction fed machine.

Which is better, friction or suction fed?

The FSN is better for medium to long runs, the FRN is good for short runs.

Can the FSN number more than once on one page in one pass?

Not if you only have 1 numbering head, if you have more, yes.

What is the difference between a rotary numbering machine and a crash numbering machine? 

Rotary numbering heads are numbering heads that turn with the machine, the numbering head goes over a ink roller and then pressure is applied between the numbering head and the bottom anvil roller to add the number (like a litho printing machine). Crash numbering is where the number comes down on the page and pushes down to make a number. Crash numbering tends to be less effective and slower than rotary.