Only Connect

Tan Dra Mon Yea
Cot Min Par Cos
Pig Sec Yam Sin
Ram Day Mil Sna

Solve this Only Connect style wall by grouping the words into 4 groups of 4. Once you have finished you can use the table below to convert each word into a number (e.g. Tan = 1) and multiply all of the words within one group together. After repeating this procedure with the other three groups, add these four numbers together. The link to the next puzzle is 

1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16

Case sensitive password provided by the next in sequence:

Tau, Gem, Can, ?