Unrecoverable error
Core v1.1.2
Mod v1.7.1
The mod Spidertron Waypoints (1.7.1) caused a non-recoverable error.
Please report this error to the mod author.

I can reproduce this. I made a save that (so far) reliably reproduces this.
Selecting any BP on hotbar will crash. Killing and restarting Factorio does not fix.
Selecting a BP-Book from hotbar does NOT cause crash. Scrolling in a selected BP-Book does not cause crash.
Deleting and replacing all BPs on hotbar does seem to fix. Any BP that was on hotbar at first crash will cause another crash.

Error while running event SpidertronWaypoints::on_player_main_inventory_changed (ID 32)
Inventory slot is not empty.
stack traceback:
[C]: in function 'newindex'
__SpidertronWaypoints/mode_handling.lua:30: in function 'convert_remote'
SpidertronWaypoints/mode_handling.lua:132: in function 'convert_remotes_in_player'
SpidertronWaypoints/mode_handling.lua:135: in function <SpidertronWaypoints/mode_handling.lua:135>

Hello, thanks for the report. Unfortunately I can't reproduce this crash. I'll put a check around the line that crashes that should prevent it, but would it be possible to have your save so that I can make sure that I'm not missing anything more fundamental? Thanks.

Yes, most certainly you can have the map save! Let me know how to get it to you!

additional mods:

Dirt_Path 1.3.5
Early-Armor-Grid 0.0.3
ElectricTrain 1.1.0
FasterStart 1.1.0
Inventory Sensor 1.10.0
katamari 0.0.3
rso-mod 6.2.0
some-disableenemygeneration 1.1.0
some-spidertron 1.1.0
SpidertronWaypoints 1.7.1
TinyStart 1.1.0
VehicleSnap 1.18.4

Wetransfer, Dropbox, google drive or similar would be fine. It may be that I can replicate it with that mod list though.

My save has 96 hours on it. :|
Sent via wetransfer.

Thanks for the save file. I can replicate the crash, and you can workaround it by removing the waypoint remote filter from your inventory until I work out a proper fix for it.

Users always manage to use things in ways that I'd have never imagined, so this will require some thought to work out how to handle it :)

NP! :)
Happy to help! Nice Mod! Thank you.
I can workaround the effects of the crash by removing and replacing BPs from the hotbar.
The only loss for me is whatever was done between saves and the time to remove/replace BPs!
(I do PLC programming, so I know what you mean!)

Basically you're not really supposed to store waypoint and patrol remotes in the inventory, they automatically convert back to the regular remote when they leave the cursor. Somehow you managed to trick the mod into letting you keep it by using a filter. I'll extend the code to automatically switch the filter type back to the regular remote as well.

This turned out to be a lot more interesting than I thought it would be! It turns out that whilst you had that remote in its filter my mod was iterating over your entire inventory every tick.

In 1.7.2, as well as stopping it from crashing, it will just leave the remotes in filtered slots alone instead of trying and failing to convert them back to a regular remotes every tick :)
However, I would still recommend using quickbar filters instead (or regular remote filters in your inventory).

Thanks! I will give it a try soon!

Sure! I like getting bug reports because it means that people are actually using my mods (and caring enough about them to want them fixed!) :D

Before updating I had another reproducible crash when selecting a BP from book.
I figured this was the perfect time to update and test.
I updated. the game did not crash when selecting same BP from same book.
First test -- PASS!
Thanks

Yep, though the blueprint-from-a-book is essentially the same as your first crash, and I had identified it as a problem. I actually reported it as a base game bug here: https://forums.factorio.com/viewtopic.php?f=7&t=93175.

I shouldn’t have been running that bit of code at that time (which is now fixed) but it shouldn’t have crashed either.

I think your mod is too overloaded.
Almost all functions are found in vanilla and are much easier to use.
Why do you need so many remote control modes?
I really like the idea of patrolling and waiting conditions.
I don't want to give them up, but the mod is not convenient, and besides, it breaks the function of following another entity, which I really miss.

Hello, thanks for the feedback. The reason that it duplicates vanilla is because those features were added in this mod before they were added into vanilla, and I haven't removed them. I may remove them and clean it up at some point, but I'm quite busy and it really isn't a priority. You can just ignore the features that you don't like.

It isn't supposed to break the vanilla follow feature, so I will consider that a bug and see if I can replicate it.

@Shaminehh I've fixed the follow entity feature, so that should work now. I'm definitely considering scrapping the waypoint functionality and just having patrol remotes as a separate item (probably behind a new technology), but it isn't a priority.

@Xorimuth Thank you for your concern for the players' requests.
In this update, I noticed that the offset waypoints are also back, making it easier to control the spider. This made me very happy.
At the moment, your mod suits me completely, thanks a lot.

Not sure what you mean by offset waypoints, but glad that you are enjoying it more :) In order to make entity following work I just made it all but ignore the remote's effects when in direct (vanilla) mode.