Lens makers use different camera mounts for their lenses. Sometimes it's possible to get an adaptor. The main problem is the film to lens distance. I've never head of a Canon to Nikon one. You should check, though. My guess is that you will not find one. I suggest that you sell your old lenses on eBay, and buy some Nikon lenses. The module for the flash is just a device that allows your camera to use it's TTL metering capabilities with the flash (you set the flash though your camera). Without it, you would have to rely on the flash's own metering, or use it in manual mode.