I know we chatted about this the other day as I was worrying about my yellow tongue too. firstly it's good that your tongue isn't white anymore (white is the candida)- although i don't know what the yellow means (I read that Chinese medicine refers to it as internal heat but I am guessing it's to do with the type of diet we have been having) but I have to say that mine has finally gone. It's been 6 months of this rigorous diet (plus all the supplements etc). I wouldn't worry about it if I were you- I discovered that worrying and stress (which of course are inevitable with this dam* thing) really do NOT help the candida and in fact I genuinely believe makes it a whole lot worse. Try where possible to put things down to die off- all too easy for me to say that now when I worried myself senseless about each and everything that went wrong as the diet progressed but I just wanted to reassure you that it will go, once you've got rid of the candida and your stomach starts returning to a normal digestive routine. Keep your diet varied where possible, not too many repeat meals too close together and be adventurous trying to get as many nutrients as possible from the things you can eat.
I don't think that a yellow tongue is a sign of a liver problem, I genuinely think it's related to your intestines so I'm sure that the milk thistle are helping but in other ways that you can't see.
I really feel for you trying to do this on your own without a naturopath- and really hope it goes well. I think at long last I'm coming out of it after being obsessively stubborn about my diet and strict about taking all the supplements- patience is soo important, even when the world around you is despairing. REally good luck.