Unclear development plan E+D or II

What I do not understand is how the knee wall with 0.5 meters is to be understood in Roman "II".

II means in my opinion a ground floor plus upper floor without attic, i.e. the knee wall would be above the II OG. Can that really be meant like this? I am attaching example pictures.

That would then be building type B in the image below. The development plan only states II with a knee wall up to 0.5 meters.

The other properties are marked with GF+attic with a knee wall up to 1.0 meter. That would be building type A in the example. Am I correct with my explanations?

Yes, it is wonderfully illustrated. Roman II means you can build two complete floors. In this case, you are only allowed to put a very flat roof on your development plan, so that there is little to no living space in the attic. Your desired house fits Bautyp B. When the individual plots are assigned to the building types, you should choose one with this type.

What I don’t understand is, how to interpret the knee wall of 0.5 meters in Roman "II".

You always have a knee wall; in the case of II, it is located in the attic. Therefore, it must not be more than 50 cm. This is a pitched attic where you can still stand upright and store things, but it is presumably not intended to serve as living space.

You can also create living space there if desired. It is 30 degrees and the threshold is directly on the intermediate ceiling. There is quite a bit of space, you would just have to keep the floor construction low. A bit higher and you can definitely fit children's rooms. And there are also dormer windows if you want to maximize the development plan.

See under Definition Vollgeschoss: this also applies to basements and underground levels, not just floors in the sense of "urban villas"