UK dispute

I am a general paractitioner, I entered in a Contract to provide Medical Consulting Services to a company in exchange for initial "incentive payment of 250,000.00" , the consideration was for me to provide medical services(clinical) for 50 hours per week and to be paid 45% of the total remunerations that my work redendered; contract was signed in Febr/2001 and was for six years service. In July 2004 I was terminated after my absence to work because of sickness x two weeks and because I produced a Work Cover Medical Certificate of 2 weeks of total incapacity and returning to work on a 6 hours per day four days per week- part time & light duties basis on which consideration I started to work in in fact I worked for 2 days when I returned on the third day I had been locked out and not allowed to attend to the medical centre, the night before I received a letter of termination of contract...which alleged that I was causing financial loses to the Company.Three years before the contract was signed I was promised something different as I started to work for this Company with no contract...there are other issues but the core of the dispute is as mentioned.
In the contract there was no Work cover entitlement, no sick leave entitlement and I was entitled only to 4 weeks leave per year...etc.