According to my information Paul is correct here. The Rolls Royce Kestrel was only used as "ersatzmotor" (replacement engine) on the prototype V-1. The V-2 prototype was already equipped with a Jumo 210A engine. Although several sources state the Kerstel engine used was a II S version however it is more likely that the engine used was the later V version as other sources mention.
All production aircrafts from the early A series (only 20 built) to the D series were equipped with different versions from the Jumo 210 engine. (Although there are some sources which state some D-version Bf109s were already equipped with the Daimler Benz DB600A engine.
I'm not sure how the engines were obtained, as various sources give different information. But it is clear that more than one engine was delivered. Most likely a batch from 10 engines were bought by the German government for a price of just over 20,000 pounds. Which was an awful lot of money in those days! But as Paul said other sources state that a Heinkel Blitz was traded for 4 Kestrell engines. The Blitz was considered a brilliant design in those days and I can very well imagine the British would desperately like to have one. According some the design of the Spitfire was heavily influenced by the knowledge obtained from research of the Blitz. (Ever looked at the wing shape of the Blitz?) A Blitz was used by the British as a testbed for Rolls-Royce engines (Registered G-ADZF), but the military version of the He60 used in the Spanish Civil war used a BMW VI engine.
The RLM (German Aviation Ministry) did not intend to rely on British build engines for obvious reasons. Therefore it is very unlikely that any other Bf109 than the V-1 prototype was equipped with the Kerstrel engine.
A less know fact is that the Junkers Ju87 StuKa prototype was also powered with a Kestrel engine as well (most likely from the same batch). This prototype was not even build by Junkers but by AB Flygindustry in Sweden.
I considered myself "well informed" on German military aviation in and before the second world war (Not an real expert as I need to rely too much on research be others) however I must confess I don't know much about Mr Churchill had said or hasn't said, but I can imagine he had to use some strong language when the public found out that two the prototypes of the most iconic aircraft from the opponent had been powered by British designed engines. And in my experience not everything said by politicians is true. However remember at the moment the British supplied the Kestrel engines to the Germans, the Kestrel engine (first built in 1927!) was at the end of its possibilities and they already knew its successor the very successful Merlin was already on its way!
Always keep in mind that when you discuss history, you look from a different viewpoint. Now you can wonder why Ford, Rolls-Royce the Germans did these things. But when the engines was supplied nobody knew what we know how. Later enemies where still potential enemies or even potential allies.
To translate it into our times: You could wonder whether the weapons would have been supplied to Iran (Persia in those days) and Irak when we had our current knowledge in those days.
But thanks for posting the link to the movie Italoc. Like Helldiver mention it is typically propaganda, but it is nice to see how people thought and were influenced in those days and it makes you think (well at least it did that to me

).
Cheers,
Huub