Well your screenshot looks a bit messy, because there is units and flags everywhere around the tile you are talking about and so it is hard to see what is going on.
Are you sure you know what you are doing with all these flags?
You have placed quite many flags there, I can see some are Worker Rally but some could be Impasse (it's hard to see).
You know that workers won't claim tiles which are in the area of an Impasse flag?
Also if you put Worker Rally at a place workers will prioritise tasks in range over all other tasks on the map.
So as long there are any open tasks in range of a Worker Rally flag workers will never do any task elsewhere until directly assigned by drop.
However Impasse is stronger than Worker Rally, meaning if both areas overlap the Impasse will deny all tasks in its range.

Can you remove all these worker flags (right click the icons) and rally units a bit away to make a screenshot which makes it easier to see what is going on.
Maybe you just had an Impasse around the tile not claimed and it does fix it for you.
But if not then please make a new screenshot and hover the tile supposed to be claimed, so we can see the tooltip of it.

Hello Rax,
can you elaborate when this crash happened?
Was it in the middle or on ending a level?
Was there anything specific you did in both cases before the crash occured?

Thanks in advance for some more details.
Cheers

We recently fixed a conflict between possession camera and camera movement and rotation triggered via Mighty Quest.
Maybe this did fix the issue in the internal version already?

Hello Karl Comrodd,
this looks like an issue with the steam works libraries.
Did you try to completely reinstall your steam client?

Alright I asked Nano and he had already fixed it but the fix is not yet in the internal build.
So don't worry it is fixed.

There were two different issues.
The one I fixed which is that units which are flying/floating above chasm could glitch through walls.
The one Nano fixed on campaign mission 13 where some siege doors were logically set to open (while siege doors have no visual open state, so they still look closed), so that units were logically allowed to pass.

Now this means that the latter isse is also present on the final siege door in campaign level 7, so it's logically open and the system allows units to pass.
I will poke Nano again so he can apply the same fix on the siege door in campaign level 7.

It might be that it was just forgotten to add.
I would still suggest to raise a ticket even if minor it would be more consistent if it can be deleted(copy spelled) by click.

Micropiglets respawn fast, if there is any drawback then it's really minor.
But surely it's not a bug.

That's an opinion but doesn't make it a bug. ;)

Arrrg, this log when it was actually unclaimed would now help to figure how this tile broke.
I guess you won't play this map again but it would be interesting if it does reproduce.
But I think it may not, at least I remember I played this map my self a longer while ago and I didn't run into this problem.