Hi Blackadder
Tandoori chicken should be ok, the yoghurt is unsweetened, also meat dishes or paneer like saag (that's with spinach) and methi (thats with fenugreek), bhuna (its a dry-ish curry) are ok, I have had dopiaza and it has not affected my and my friend's bg at all (was just fried paneer with peppers, onions and spices), ask what is in the sauces, if they are thickened with flour then they would have more carbs obviously.
Stay away from the indian breads, you are ok with poppadums, they are gram flour, as hanadr already said, and obviously rice is a no no, but honestly try to have your curry with cauliflower rice and you will see that it works really, really well, I was not sure at first, but even my non-diabetic friends often use cauliflower rice, esp as it is a good way to get extra vegetables.
On the whole I think even the curry sauces are ok, many are thickened with coconut or cream, as I said you just need to ask about the ingredients.
Enjoy your take away.
All the best
Karen