When a probe droid(or any mobile) is in blocking terrain(maybe wrong name, but it's red) can it shoot from the space it occupies as if it was a normal space?

When there are adjacent difficult terrain spaces do you need 1 extra movement point tor entering each of them(so if two such spaces 2(enter)+2(enter other)+1(exit) or 2+1+1?)

How does the first question work with massive figures?

Yes. A figure on a space with blocking terrain can draw line of sight out of that one space. (But note that blocking terrain edges block line of sight, because the figure is not occupying the terrain between spaces.)

Yes. Only the space a figure enters is considered when determining the movement point cost. Difficult terrain and hostile figures incur the cost depending on the spaces the figure enters for each moved space.

Mobile and Massive work the same way when considering blocking terrain.

See also: https://community.fantasyflightgames.com/topic/247683-counting-spaces-blocking-terrain-and-mobile/