Update: Thanks to Qon !
Replacing defines.inventory.player_... with defines.inventory.character_... in the cheats.lua worked.

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The mod Creative Mod caused a non-recoverable error.
Please report this error to the mod author.

Error while running event creative-mod::on_tick (ID 0)
real number ...

Factorio 0.17.29 (build 44443, win64, steam)

Loaded savegame after update. Game Crashed to desktop with Messagebox about a logfile. No Mods in savegame.

2nd try: opened and closed the Blueprints with "b" couple of times. Game crashes.

Abnessor, I confirm the behavior. If you start with 50 undergrounds, place all, Start the run, Go Back to building, you get another 50.

"You get infinite items anyway" - Klonan, what is meant by that?
If player startet with 50 undergrounds and used 50, no more can be placed unless player goes to ...

Thank you! This was hard to see.

For anybody maybe searching this topic:

Behavior in Factorio 0.17.11: Car lost when picking it up with full inventory

How to reproduce
- Full inventory with car in it
- Place car from inventory on map
- Pick up an item to have a full inventory again
- Try to pick up car
--- Message that inventory is full and car is gone from map and not ...