There is reproducible bug, where game can be crashed trough lua, in either TransportBeltConnectable::drawStartingPiece TransportBelt::updateRotationPoint or Wall::draw,
If a belt or a wall is placed by robots, trough a blueprint, from a custom blueprint.
Steps to reproduce:
1. Install only one mod, https://mods.factorio.com/mods/mickael9/cut-and-paste, and update "factorio_version" to 0.16, add icon_size when necessary.
2. Start fresh sandbox game, enable cheats and all research.
3. Get a power armor, portable fusion reactor, personal roboport and a bunch of construction robots.
4. Build a setup like here, belt must be full before you continue
![Image](https://forums.factorio.com/images/ext/9fdb1bef04743d0bfb308fbdd34bbb84.jpg)
5. Spawn the player, put the power armor on so you can use robots.
6. Unlearn all the research
7. Proceed as in the video ( there was a pause because game didnt crash right away this time so i was surprised, but it just started doing weird things with belts, and it crashed eventually after i stopped recording. ):
https://youtu.be/6ElgWvMHPYE
You can see the weirdness goin on.
Similarly, the crash can be reproduced using the same custom blueprint mod on stone walls, when building them close together. Wall segments should connect but they don't and the game crashes.