I change some settings and the game crashs:

3245.665 Error MainLoop.cpp:1284: Exception at tick 79807862: The mod Autobuild (0.5.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event autobuild::on_runtime_mod_setting_changed (ID 60)
autobuild/control.lua:37: attempt to perform arithmetic on field 'build_distance' (a nil value)
stack traceback:
autobuild/control.lua:37: in function 'change_visual_area'
autobuild/control.lua:503: in function <autobuild/control.lua:483>
3260.158 Quitting: user-quit.
3260.847 DSound: Stopping voice
3260.847 DSound: Joining thread
3260.850 DSound: Exit _dsound_update; tid=10236
3260.850 DSound: Waiting for voice to stop ... signaled
3260.851 DSound: Joined thread
3260.851 DSound: Destroying thread
3260.851 DSound: Thread destroyed
3260.851 DSound: Releasing buffer
3260.851 DSound: Voice stopped
3260.851 DSound: Deallocating voice
3260.851 DSound: Deallocated voice
3261.014 Steam API shutdown.
3261.028 Goodbye

Thanks

Thanks for the report.

I assume, you have disabled the construction via toggle (or not yet enabled) and change settings opacity setting?
You could try, if you have more success, if you enable the construction and change opacity then.

I also have detected a problem, when loading a save after factorio/mod update, where the construction is disabled, although the area is yet visible. If you try to change opacity setting, you also get the same error.
It's even a bigger problem, because the original area is visible and can't be hidden anymore, because it is orphaned. It draws a new area, which is overlapping and intensifies the area.

If have to look into for a fix and how to remove the orphan area.

I already uninstalled this mod!
I don't really understand what this mod does and it appears to be doing nothing in my game. Because of that I try to change some settings...

Ah, ok. Before this mod does anything, you have to toggle the automatic construction. Either enable it with the button in the toolbar with the wrench symbol or use shortcut Shift+B.

This should be fixed now