Well, let me explain to you then.

as i mentioned in the first post I use it on my motorcycle! Garmin Zumo has the feature to disable recalculating! and you ask why? exactly because in motorcycles we don't only want to reach from point A to point B on the most easy/fast/short way. We want to go sometimes for a specific route (for example with lots of twisties) and for that you can create your own route on BaseCamp. this created route is created to be followed! the problem is that if we for some reason mistaken the correct designed route (wich is really easy in my country) The GPS recalculates the route for a completely diferent one and stop following the specific created route.

well. hope now it is clear the issue, that i believe that is not nonsense! (or else zumo didn't had this feature)
i only wnat to know if i can have it also on my Nuvi, or reinstall a firmware of Zumo (and yes, it is possible to pass from Nuvi to Zumo firmware. it is here on the forum, but is not for my model 2495, and i'm asking for help to know if it can also be done to mine)

thanks