According to Messerschmitt; Aircraft Designer by Armand van Ishoven, the M 32 was a very unusual "weekend" amphibian NOT designed by Willy Messerschmitt but some other unnamed individual.
It would have had two diesel buried in the fuselage driving a single prop mounted above the center-line, and would have used a rocket for take off boost. I could swear that I've seen this posted elsewhere on the forum, but cant seem to find it with the search feature.
This data also conflicts with what is posted in the messerschmitt designation thread, that states the M 32 was a biplane trainer that later became the He 72. This is somewhat in agreement with Willy Messerschmitt: First Full Biography of an Aeronautical Genius by Frank Vann, which states that the M 32 was for a biplane trainer that progressed no further than a few early drafts made by Messerschmitt himself. Quite confusing no?
The M 33 was for another novel design. Vann states that Willy was inspired by the Volkswagen, and decided to make a peoples plane, using a DKW 15hp engine and sold as a kit for home builders. Like the M 32, this progressed no further than the mockup stage. This mockup was shown off at the 1932 DELA (Deutsche Luftsport-Ausstellung) exhibition in Berlin, along with mockups of the M 32 and M 34. Hopefully this info leads to some pics of that M 34, which very well could be sitting behind the 33 in the attached pics.
Lastly, I am including an excerpt from Vann. This is a section of notes Messerschmitt prepared in response to a request for an article from the magazine Deutsche Technik in July 41. While this isn't directly related to any projects, it does give an idea of his thinking at the time, and many of the ideas mentioned in this would later be tried out in some way or another during the war. It is also interesting to me that he specifically mentions steel for construction of high speed aircraft and this may in part explain Messerschmitts preference for steel later in the war when materials were running short.