Nearly killed myself - Dangers of running too low

[Dave]

preceded to slide for about 10 meters on the underside of the car at the front so neither front wheel was making any useful contact with the road ...
... Im gonna have to wind the coilovers up when it stops raining. I know she looks stunning at this height but I nearly had a heart attack.

You didn't have them setup correctly! your overall vehicle weight on plummet overcame the travel required of the springs to equalise the force the drop of your car had.... your springs don't have the force to make traction with the tyres!