Id like to make a custom study on Sierra charts. Using the color bar based on alert condition, a study that would plot a point if the current candle opens outside the range of open and close of the previous candle? High or low wouldn't matter, as long as its not opening in the body of previous candle?

thank you

Try this:
=OR(AND(C[-1]>O[-1],O>C[-1]),AND(C[-1]<O[-1],O<C[-1]))

You can learn to do this yourself:

With Simple Alert syntax, the OHLC of a bar is:
Open = O
High= H
Low= L
Close=C

Previous bars are located with a [-1] suffix:
previous Open = O[-1]
previous High= H[-1]
previous Low= L[-1]
previous Close=C[-1]

OR and AND functions are opened and closed with parentheses ().

The Close of a [previous] candle is at one side of the candle body, either at the upper or lower.
If it is at the upper, then: C[-1]>O[-1] and the current open must be greater than the previous close: O>C[-1]
If it is at the lower, then: C[-1]<O[-1] and the current open must be less than the previous close: O<C[-1]

Since either can happen, they are combined with OR.

To make it visually easier, you can use spaces to separate sections:
=OR( AND( C[-1]>O[-1], O>C[-1] ), AND( C[-1]<O[-1], O<C[-1] ) )

Thanks, just what I was looking for.