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I have couple of questions related to the LTC2986/2986-1 

1)As for the anti-aliasing capacitor, it is recommended to be 100pf in the data sheet and that's the value you have used in the evaluation boards DC2618A and DC2508A, however in the datasheet in pages 1,26 and 30 when you drew schematics for the thermocouple you used 0.1uf. Is it better to use this value with thermocouples or the 100pf would be enough?

2)In the evaluation boards DC2618A and DC2508A you connected the COM to the ground via a capacitor and not directly as mentioned in the data sheet. In the universal protected board DC2507A the COM is directly connected to the ground. Is one of them better than the other?

3)In the datasheet it is mentioned to tie all the VDD together and connect them to 0.1uf and 10uf parallel capacitors. In the  evaluation boards DC2618A and DC2508A you added 2x10uf and 4x0.1uf. Is there a specific reason for such number? if I am gonna added extra capacitors infront of each VDD for better stability would you recommend a specific combination?

3)If I used COG capacitors instead of the recommended X7R for the Q1,2,3 pins, would there be any problem?

4)In the evaluation boards DC2618A and DC2508A, the extra 1ohm resistor and 10uf capcaitor connected to the VREFOUT/VREFP pins, It is mentioned in another question here on the community that it is from an old design, would adding them improve the functionality of the IC or removing them won't affect it at all?

5)In the evaluation boards DC2618A and DC2508A, the VREF_BYP has an extra 10uf capacitor parallel to the 0.1uf recommended capcaitor, does this improve the design or removing it is fine?

6)If I will add multiple single ended thermocouples, would you recommend against joining their free ends together and connect them to a protection resistor then to the ground? or it is preferred to have each leg with its own protection resistor that is connected to the ground

I really appreciate your help and sorry for the long post as I have been trying to collect all my questions to ask them at once
Thank you