Here the answers:
What does your network look like?
2 Computers connected to the FSG (the FSG is a NAS and a router).
Is there wireless involved?
Yes. 1 Computer connects with wireless, the other directly with an ethernet-cable.
How are each of the units (PC, router, FSG) connect to each other?
Through the FSG.
What kind of wireless router do you have?
As already said the FSG.