Hi Erel,
The project won't work; you'd need a facebook account, contacts who uses the app, an access to an mqtt server... very complicated to get it work. I've made a small project with the same layout (a class, a module, the assignment made from the class's initialize sub), but it works OK, no exception is raised. The GetMap sub, on the "big" project, is also called from other process and no error is raised either.
Thank you very much for your answer! I'll keep debugging.