Piano allenamento per mtb

In what way should it take a circuit into account? What is the goal for your training for that curcuit? Isn't that a race? You can create your own race and it doesn't have to be public.

se io partecipo ad una serie di gare durante l'anno, garmin nel programmare il piano di allenamento tiene poi conto delle successive gare e prosegue con il piano? o si ferma alla prima gara  inserita?

The training plans are only for a specific race. It will end when the race date is reached. The idea is that the training plan will get you in optimal form for that race.

If there is short time between the races then you will just have to maintain the form during race season.