Hi Mr. Rézeau,
I' m a enthusiast of the use of the Moodle's Lesson resource and lately I have developed different applications with it. In my view it is one of the most interesting tool of Moodle. It can give you more control over the content and allow you to follow the students through of their own learning route. But, this tool has some limitation over the capability to interfere on the files CSS of Moodle's themes, and also the dificulties of deal with HTML code on their edition mode, several html codes as area map, background image etc are not accepted by this resource. I'd been studing how it could be enhanced. I've been thinking in some kind of plugin that could give to users better to edit HTML capacity. I would like find more people interested on this tool to share experiences and sugestions. I am developing a module tool starting from the Lesson code, called SmarLesson and soon would like put it available here to test. Gracias! Adriano