Michel, is it possible you’re not using a widget at all but rather a shortcode? It looks to me like in the right hand sidebar you are using a widget, which can be modified as we discussed. But, in the content area perhaps you are using our shortcodes instead? If so then it is actually much easier to modify the event limit.
Edit the page, and find your shortcode. It will probably look something like this:
[tribe_events_list]
And just add a limit:
[tribe_events_list limit="25"]
Was that the problem? If so I’m sorry I didn’t think of that sooner. We kept talking about widgets, but I should have been more perceptive to realize it might have been a shortcode instead.