Support/resistance indicator, long term cooperation opportunity

Hello,

I am in need of a support/resistance indicator with the following features:

 - CPU efficient (major calculations have to be carried out once per bar, calculated levels should be stored as variables and not re-calculated on each tick), it is important that the indicator could be used on several charts simultaneously;

 - buttons in UI which can be used to change inputs/parameters of the indicator, the indicator has to be able to recalculate once parameters are changed.

 All of the rules the indicator has to follow will be given in private. This is a part of a bigger project, if I like what I'm getting from the developer, more work will follow.

Let me know of your experience. Good communication in English is mandatory!