Attention professional painters: can you help me?

I bought a 5 gal bucket of Kilz 2 latex primer. There was no seal under the screw off cap. I used it on an entire room. Whenever I would over lap with the roller it would come up in clumps. And now that it's dry it has little alligator cracks in most of it. I took the bucket back and got a new one. Now what should be my next step? Should I just go over it with the good stuff or try and take it off? And if I should take it off how do I do it and what do I use?