How long does updating a Net3 Gateway take?

Not a dumb question at all. It should be pretty quick - like a matter of 30 seconds to send the file and done in a couple of minutes. So something is wrong. What I would do is reset the gateway (you can do this by pushing the reset button on the front) and try again. This might be caused by network infrastructure (if data is getting lost in the network), if that's the case may be worth connecting it directly to the console with a network cable, bypassing any switches and other stuff you have on the network.

Good luck! As always feel free to call tech support if you get really stuck

I have 4, 1-port gateways and they took hours to do the bootloader update over Net3. 2 of the Gateways have 6 ColorSource PARs attached and the other 2 have 8 PARs each attached. I don't know if it matters how many fixtures are attached to the gateways or not. Once the bootloader was updated, the fixture colorsource family update was way quicker (even as it updated each fixture attached to the gateway). 

I did not connect directly to the gateway, I just ran it through the Net3 connector, which I assume then ran through the Paradigm controller and on to the gateways and fixtures. In UdaterAtor it does suggest connecting directly to the gateway to reduce the update time, if I remember correctly.