I've seen it.
It is actually about the controversial actions of captain Raymond Westerling. His "Westerling method" for pacifying insurgent areas meant surrounding a village, rounding up the men and executing suspected insurgents on the spot.
The portrayal of events in the film has led to protests and calls for a disclaimer from several groups in the Netherlands.
I have no intention of starting a political discussion here, just pointing out that you won't find any of the major military engagements between the Indonesians and the Dutch in the film.
The uniforms, weapons and vehicles used in the film are historically accurate, except for the dark uniforms of Westerlings special troops. In reality they wore ex-USMC duck hunter fatigues.
T.