Given his girth and venality, the character of Himmler seems to have been based more on Hermann Goerring than Heinrich Himmler. Himmler had a rather slight build.
When Karel meets Jamilla's mother for the first time, there is a moving shadow of the boom microphone on the pillar above and behind them.
A bus lists its destination as "Prague" A local bus would have used the Czech spelling of "Praha"
Heydrich was ambushed in the city of Prague, not on a country road. His travel plans were also no secret: despite Hitler's admonitions Heydrich always took the same route when traveling in the city, believing the the people were too cowed to dare attack him.