Scene Composer - mouse picking

I’m curently working on a plugins who will serve to generate an hexgrid directly in the sdk using the sceneComposer. Currently i got some issue to edit the grid once generated since, i don’t understand where i’m suppose to get the user input when using the sceneComposer. When using/runing the plugins at the current stage i can see that there is a mouse picking already running in the background (basic behaviors of the scene Composer, the cursor showing up is the one used to link object to the scene). I want to keep the current behaviors of the sceneComposer but extends it to update the grid at the same time.

Following the wiki i’ve guessed that i needed to do the steps at "“Requesting the Scene” to get the control of it. But still following the wiki, doing this will remove all current behaviors and let the user(me) handle everything manualy… That isn’t realy what i’m looking for since the current SceneComposer work fine most of the time.
Then there is the “Listening for Node selection”… i’m looking for a worldPosition() so it’s a bit out of context.
link : sdk:developement:scene.

Btw the plugin work with an AppState handling the grid and i want this AppState to get the user input…
I don’t know if i’ve explained myself pretty weel feel free to ask more details, have a nice day.