Picked up my normal remote after testing the patrol remote. It was already linked by I clicked the spidertron it was linked to anyways:

The mod Spidertron Waypoints (1.1.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event SpidertronWaypoints::on_player_used_spider_remote (ID 166)
core/lualib/util.lua:49: attempt to index local 'position2' (a nil value)
stack traceback:
core/lualib/util.lua:49: in function 'distance'
SpidertronWaypoints/control.lua:75: in function <SpidertronWaypoints/control.lua:62>

Thanks for the report. It should be fixable, but that is the most unreliable part of the logic due to not having https://forums.factorio.com/viewtopic.php?f=65&t=88668. Come on Wube, we need 1.1 now!

If you place 2 sequential waypoints close to each other (<5 tiles apart) , all waypoints will be lost when the spidertron reaches that area. This is a limitation of the API, and will be fixed in Factorio 1.1

You can't blame the crash of the mod or the bug that waypoints disappear on a missing event. These can be fixed now and are not related to that at all :/

You're right, it probably could be fixed. However, the logic is quite complicated, and would be made way easier with the upcoming event :) I'll see what I can do.

Ok, sounds correct so I can understand that :)
GL HF

I managed to fix it. The reason that I left it how it was before was because I wanted to assume that if the autopilot_destination was missing, it was because the player had manually moved the spidertron, not because it had arrived before my on_nth_tick had triggered. I've essentially reversed it so it assumes the latter before the former, but it still actually still supports manual interruption as long as you hold the 'move' button until you are further than 5 tiles away from the grouped waypoints (most players will never notice that it isn't quite correct).

I wasn't able to replicate your first crash, but I've cleaned up that code anyway in 1.2.0 so it is probably fixed. The issue of disappearing waypoints is also fixed as described above :)

Nice :)