[Dreadstar]

Unfortunately,spike tyres never last very long on tarmac,they're really meant for running on dirt/grass/astro,so they don't get a lot of grip on damp/wet tarmac. Is this B4 brand new,or did you get it 2nd hand?
Every time you decide to take it out to either race,or bash it,go around every screw,making sure that they're tight,it's amazing just how often,that you'll find some slackening off. I wouldn't worry about the play in the shock ends,as long as they don't pop off the balls very easily they'll be fine. They should pivot around the balls in normal use anyway. Were you running on spike tyres all round,or just on the rear? If you do decide to run it on tarmac again,I'd suggest puting the grooved front tyres on it,as they'll work far better on tarmac than spikes will.