Yea, sorry about all this mess, and thanks for the review.

I have integrated the suggestions except the one with the gap to not edit the building geometry.
I don't know if that is possible in OsmInEdit or ID (if it is, I have not found a good way).
That might push me towards JOSM, as OpenLevelUp! has been somewhat of a pain to use. I did not notice the weird non-snapping on the different layers when using said editor. There might be a "let's square this room" issue.

About tooling: What editor would you recommend for indoor mapping? OpenLevelUp does not support corridors (only footpath) and adding them in Id is nearly impossible.

The big plan with NavigaTUM is that I want to finally solve the nav part. (Originally, we thought that might be simpler ⇒ this is why that is in the name ^^)
After the frontend-rewrite and submitting my thesis, I now have the time to work on this.

This also solves/simplifies the feedback problem, that changesets like "hey, I went around all(!) of TUMs bathrooms and your data is shit on them. Here is a HUGE excel list" to a simple watching for the minutely OSM changes, notifying for relevant ones and addressing issues particularly relevant to me/TUM.

Sorry/thank you so much for babysitting me through this journey and for the tips <3 
If you are sometime at the MPIC student council in the Maths/Info or Physics buildings or at the ASTA on the main campus, please feel free to book a beverage/coffee on my account (Frank Elsinga).

My first plan was to get to know the OSM-data model, improve the pedestrian routing a bit and integrate some sort of proprietary indoor pathfinding on top of our CAD data plus a outdoor routing engine like valhalla (2).
Then I watched (1) and noticed that there is a simpler way that also makes it simpler for successor systems (let's be honest: NavigaTUM will not be the last Roomfinder)…

My plan is to
- upload our BIM-Data in a redacted form
- or (if TUM's building department does get cold feet and Accessibility/… can't convince them) go around and measure buildings in the summer

The advantage of the plan is that this makes this into something that "the Product" can scale outside of one's Higher Education Institution's custom infrastructure (⇒ to other TU9 Unis like LMU, KIT, …).

By redacted, I mean not to publish the layouts of our “critical” infra:
- any info about our employee housing,
- Sensitive/unsafe things for others like gas storages, biolabs, …
- "where people might get bad ideas" (some departments deal with animals or crops)
- "which we don't think people should care about"
  (hint: buildings don't have thicker walls behind elevators or behind entry doors ⇒ hiding actual critical infra)

⇒ My plan is to map the first two floors manually and then one with the proper BIM to gain experience with the tools in this space.
⇒ "tagging" names, urls and room usages should likely be done via a custom tool or integrated into Navigatum to keep this part up to date with OSM (I know the part about automated edits and I am going to follow due process)

PS: Yes, copyright for this building has been negotiated with the rights holders.
PPS: OpenSource @ TUM e.V. will obviously financially contribute a bit [we are small] to OSM or the local group [have not been at their meetups] for the infra/human cost that encouraging new users to contribute on building geometry issues/.. issues brings with it.

(1) https://youtu.be/wfLJit4etI8
(2) https://github.com/valhalla/valhalla