Hello CommanderStorm,

because of review_requested:
I'm sorry to say, but the edits of the StudiTUM got a big mess.

- Just in case you didn't see it already a link to the wiki description of the indoor tagging: https://wiki.openstreetmap.org/wiki/Simple_Indoor_Tagging

- you changed the building outline (the building has an irregular shape now instead of being rectangular). --- The easiest way to avoid this is by keeping a small gap between the indoor=rooms and the building outline like e.g. here (1).

- There is a chaos of intersecting highways. --- For corridors inside buildings highway=corridor (2) is used instead of highway=footway. Moreover these corridors should be drawn nicely and not as a bit intersecting mess.

- Out of curiosity: Are you planning to use the indoor data for NavigaTUM?

Best regards
map per

(1) https://www.openstreetmap.org/way/1081837285
(2) https://wiki.openstreetmap.org/wiki/Tag:highway%3Dcorridor