While the answer partly depends on who you consider an “officer,” the answer to “was it commonplace for these people to be arrested?” is that it couldn’t really have been considered “commonplace”, but it certainly did happen. There were many arrests, but there were also many officials and leaders within the National Socialist German Workers Party during the Hitler years. These ranged from people who joined for the associated the career benefits to the vilest extermination camp officials. Ascertaining the crimes of each and every one of these card-carrying Nazis was a daunting task, and it simply wasn’t practical to arrest millions of people solely for being NSDAP members.

Many of the most shockingly cruel and fanatic Nazi officials were indeed arrested and put on trial after the war. The “arrests” were often “captures” conducted by Allied soldiers during the last days of the war as millions of German troops and Nazi party members surrendered (whenever possible, they surrendered to the British or Americans). Other Nazis were arrested by Allied troops during the post-war occupation as well (GIs and Tommies in post-war Germany to a large extent functioned as local police.) Some of the guiltiest Nazi leaders, like Joseph Goebbels and Heinrich Himmler, committed suicide at the war’s end while others escaped via “ratlines” to places such as South America.

The highest-ranking Nazi leaders in custody (Göring, Hess, Dönitz, Speer, et al) were put on trial before the famous Nuremberg tribunal. This was not the only such trial, but it is the most famous of them. Many other trials were held in American/British-controlled territory and in Soviet territory as well. These included the trial of Auschwitz commandant Rudolf Hoss, who was found guilty and hanged on the site of the camp itself. There was even a trial specifically for female concentration camp guards such as Irma Grese.

Ultimately, however, many Nazis were never brought to justice. This was due to a combination of factors including the difficulty of gathering evidence, the sheer number of potential defendants, and the increasing focus on the burgeoning East/West tensions that would define the next several decades. Much of the crime scenes, witnesses, and evidence was also located in the Soviet-controlled zone of Europe, and this fact did not lend itself readily to prosecution. The Americans & British also needed West Germany as an ally in the new NATO alliance, and it was hard to garner support for years of litigating a painful chapter that many preferred to forget. The need for positive relations West Germany (not to mention a re-armed West Germany) also prevented more extensive prosecutions of Waffen-SS veterans and regular Wehrmacht veterans, a great many of whom committed grave war crimes and/or participated in the Holocaust.

I am not familiar with the film you mentioned or any such camps, perhaps someone else can chime in.

tl;dr Allied troops captured/arrested many Nazis and these were put on trial and many were imprisoned and executed. It was ultimately a incomplete justice, however, as many guilty Nazis escaped trial due to a variety of reasons.