Upgrade my Script to do multi-function display

a.) My current Script can do the Followings, 1.a) Create an index; 1.b) Create a custom configuration chart.

b.) What i want is to assemble all indexes and make an average index(Avg Index= index1 + index2 + index3 + ........../ no: of indexes)

We will call this average index "APX"

c.) Then we will configure another custom charts whereby we will say 1.) APXAUD=APX/AUD Index; 2.) APXCAD=APX/CAD Index; 3.) APXCHF=APX/CHF Index;

4.) APXEUR=APX/EUR Index; 5.) APXGBP=APX/GBP Index; 6.) APXNZD=APX/NZD Index; 7.) APXJPY=APX/JPY Index; 8.) APXUSD=APX/USD Index

d.) Then we will try to create custom pair again say "APX/LNC"=APXAUD+APXCAD+APXCHF+APXEUR+APXGBP+APXNZD+APXJPY+APXUSD/8

This will be our Structured Currency......

e.) Then we will try to find the value of LNC per Fait of currencies in our index pairs.

i don't know how to go about this, i want something like a.) LNCAUD= [AUD Index] - [APX], b.)LNCCAD= [CAD Index] - [APX] and so on and so though