The side effects of simvastatin include myopathy (muscle disorders and pain) and arthritis. However it is not possible to say if your finger pain and stiffness is due to simvastatin or independent of the treatment. One way is to stop simvastatin for a few weeks to see if the pain and stiffness disappear.
Your weight is more than normal for your height and age. Reducing it to something like 65kg will be helpful.
There is no use taking B-complex vitamins unnecessarily. Normal diet is adequate.
If you are referring to Flax (not Flak) seeds oil, it contains Omega 3 Fatty Acids which is known to reduce triglycerides. However I cannot comment on the efficacy, safety and quality of the specific brand. It may be worth taking a modern preparation of Omega 3 Fatty Acids.
Despite one years treatment with drugs and lifestyle changes, both the total cholesterol and triglycerides have not come down appreciably to the expected extent. Your TG level is still quite high. May be your doctor can try one of the fibrates.