Need some help!

Just had my first major problem with my 2003 G35. I was driving along and all of a sudden I had no clutch pressure. I pumped the clutch and feels like nothing is there. Normally it's REALLY stiff as I have a Nismo Performance clutch but absolutely nothing.

I checked the reservoir and it was below min. I filled it up and tried to pump the clutch and you could see the fluid leaking out below just behind the firewall or beside the left front tire.

My mechanic, tow truck driver and a buddy of mine think it's the clutch slave cylinder given the hose is intact, the master cylinder had no sign of fluid on it and the fluid is coming out basically at the bottom of the car.

So my questions are:
1) Is it most likely the clutch slave cylinder?
2) Should this still be covered under warranty? Powertrain is good for 6 years/70,000 miles but is the Clutch slave cylinder considered part of powertrain?
3) The car is orginally from the US....would the warrantly still be honoured in Canada? I haven't done any service at an Infiniti dealer since I brought it over...i've been going it at Ajax Nissan but they've told me they can't do any warranty work on an Infiniti.
4) Is this an easy enough DIY job to replace the clutch slave cylinder?

Any thoughts would be appreaciated.