On right hand bends you're loading up the left wheel, on Left hand bends it'll be the right wheel.

Did you keep your old drive shafts ? It could be bad luck that one of the drive shafts you've put on is knackered as well. It could be worth refitting your NS drive shaft.

I've fitted Vibra tech engine mounts & they do cause a bit of vibration when new but that goes away once they loosen up a bit. As long as they have been fitted correctly they shouldn't cause a problem.