Hi !
I will try to explain with my poor English.
By custom symbol with a study i mean an indicator (like instrument ratio or spread that already built in indicators, but they are limited to two symbols)
that can measure the relative strength in percent between desired instruments.
Let me explain further:
let's say we want an Usdx like index, so we add -EURUSD, +USDCHF, -AUDUSD, -NZDUSD, +USDCAD, +USDJPY, -GBPUSD in percent or pips, so we have a USDX like symbol.
I hope that that is explains what i mean .
Thank you!