Candida is always an issue with Mercury, IMO this gets better when increasing the dosages using the Cutler intervals. I don't see you talk about how many hours you space your chelation at night. With heavy Lyme and Hg toxicity you can be better off increasing your frequency at night. You won't sleep anyhow, at least with the chelation you may get some deep sleep.
Couple of old posts, the last one is why I always rant abou not treating Lyme without Treating Hg but there are more rants like that in the Rife forum history.
Mind and Head - Metals
The importance of mercury detoxification when treating Lyme Disease