[tc4332]

To try and clarify that.
If you have a bulb or a fuse in your hand you would use "continuity" to check if they were good or bad. Open circuit or very high resistance would mean no continuity therefore blown bulb or fuse. Do not use continuity on live circuits.
What you need to use in your case is "voltage". Set the multimeter to 12 volts (probably 20 volt or 30 volt scale), connect the black lead to the vehicle chassis (most bolts would be at earth potential), then proceed to touch the red lead to various points in your circuit. Hopefully you will read nominal 12 volts at good points and zero at bad.
If checking a complicated circuit it is always best to make your first check in the middle. If the reading is good then the fault is in the final half, if reading is bad then the fault lies in the first half. This tells you which direction to make your second check, splitting the suspect area in half each time. This is mathematically the quickest way to find the problem.

I know, all boring stuff. Good luck with it. A short should only blow a fuse or cause a circuit breaker to open, it should not "fry" anything. Of course if the short was inside a module then anything could happen but in your case all you did was short the fusebox supply to earth so major supply fuse blown instead of minor circuit fuse. Any other symptoms should be circumstantial.
But then I'm only a boring old fahrt so what do I know????