If a hero have ENDURANCE = 5 and have no strain, but decides to rest. Can the hero recover any damage up to his Endurance number even if he suffered no strain ?

In this example, if the hero have 5 Damage and 0 Strain in this case he could recover 5 damage ?

yup yup yup

Elaborating

Strain in a campaign (RRG page 23, 3rd last paragraph):

• If an effect allows a hero to recover more [strain] than he has suffered, he recovers one [Damage] for each [strain] he cannot recover.

Too easy for a hero to recover damage.

How conditions ara applied to Droids ? Droids shold not be stunned or bleed. Any restrictions described in the rule book ? I have not seen any.

It is easy to recovery but its also easy to deal damage. If the imperial player spreads the damage around don't expect to wound any of the rebels. If rebels spend all their time healing don't expect them to beat any time limits

Droids can leak fluids and computers lock up and need to be reset.

Changing subject ... What if I decide to close the blast door (in campaign´s first mission) but I have heroes standing where the doors should be placed. Should I move the heroes ?

Changing subject ... What if I decide to close the blast door (in campaign´s first mission) but I have heroes standing where the doors should be placed. Should I move the heroes ?

First, the door should go between squares, not in the middle of the squares, so you shouldn't have to move heroes since they are small and fit into one square.

If, however, a large figure is standing over the line where the door goes, read the fifth point under "Doors" in the Rules Reference Guide.