I'm organising the Libre Graphics Meeting, a gathering of developers and users of free software graphics applications, in CPE Lyon, next March.
I heard from someone on the Inkscape project that you might be interested in having a gathering there, since you have an office in Lyon, and most of the developers are in Paris.
If anyone from OpenCascade is interested in coming (and why not, helping with the organisation?) please contact me by e-mail and we'll take it from there.
The only ressource we have at the moment for the event is in the GIMP's wiki at http://wiki.gimp/org/gimp/LibreGraphicsMeeting - we will soon have a site.