I came across this scenario well playing...

I win an intrigue challenge and play condemned by the council, my opponent plays they shall not cross, I cancel it with harrenhal, then my opponent plays an other they shall not cross to save the location. So my question is do u get multiple chances to save/cancel something or do u get just one chance?

You get as many chances to save/cancel something as you like. You have to use a different save/cancel effect for each attempt (which your opponent did - two separate copies of the same event), but you can make multiple attempts.

Thanks