Dem,
What can I say mate, I am gutted for you..!! As we have all said this guy knows nothing and seems to be bent on bringing the company down to be a mino in the market, you don't want to be part of a company sliding down hill. I know you did not want to leave as you felt safe, but this guy has done this all the wrong way, as expected. You have an excellent case against the company, go for the throat, no deals and don't back off. It is probably the best thing that could have happened, I know you don't think so now, but you will as time goes on. Staying with this company with this guy in control was doomed to fail and you are best out of it. Pity you lost the other chances, but put yourself back out there straight away, you did it once, you can do it again.
Make sure you have all your records of pay and commission ready for inspection, along with your contract. Try and put all the sales that you can remember down on paper for each month you were there, so that anyone can see your performance. The company will probably try and cook the sales records as soon as they know you are coming after them, so get as much info together as you can. Put a portrayal of the rest of the staff in the office together, timekeeping, sales performance etc., so that you can prove who was actually doing what should be done. Don't sign anything from the company, accept any payments they send you on a provisional basis only and keep copies of everything.
I am almost as angry as you are at this ar5ehole, he now really does deserve everything you can throw at him. See if he is on facebook, it's surprising what people will let slip..??
Keep well and chin up mate..!!
Cheers
R