I wish to thank all of you for yours knowledges and yours shares.
Special mention for Andreas
You will recognize pieces of code you have shared.(userinteract,how to compare groups,how to collect and many things).
This plugin is intended to do same things as plugins preset to qlist and preset to executors in ma-share gma2 lua plugins.
I hope that the names of functions are enough clear to understand how the plugin works.
You must have an active selection of fixtures which will be compare to existing groups to grab the name of group.
The qlist is labelled with the name of the selection and the preset type, executors are labelled with name of the selection and presets.
By default fade time and offcue is set to 3 seconds (lines 156,160,180,184)
For sure I am not a programmer so this plugin could be more elegant and less longer.
Feel free to re-write it and share again.