As said at another report. There is plenty of ways to damage an allied player.
You should not ally with anyone you don't trust.
Limitting these things would limit also ways to cooperate with your ally.
This is not a bug.

This is a different game with own mechanics and we do not support to build bridges just where you have view.
It is always required to connect them to your claimed land.
Other than that you should be able to drag rooms form an invalid location towards a valid location.
The issue with partially completed rooms I might not fully understand, but as far as I do it was in no dungeon management game from the past possible to drag rooms over unclaimed tiles so that the room is placed after claimed.
If this is what you mean, then it's a feature request/suggestion and not a bug.
Please raise suggestions here:
https://forum.subterraneangames.com/forums/suggestions.10/

This is a known issue which will be fixed in next patch.
It is only happening on some siege doors in campaign level 13.

When you are allied with someone you need to trust him.
There are a plenty of other ways to damage your ally and preventing them would limit the ways to help each other a lot.
So this is not a bug and changing this would bring more drawbacks.

I agree that the heal spell shold support healing allies, but disagree it should heal enemies.
The problem is that Heal is an AoE spell in this game and you could accidentally heal them.
However this is not a bug but a feature request/suggestion.
We have a suggestion forum:

https://forum.subterraneangames.com/forums/suggestions.10/

Of course they gain experience from combat and they regulary fight with other workers.
This is not a bug.

That is intented, because if we would prevent it other people would report that they can not remove these alerts.
They do not provide any functionality but information, every player is free to slap them away after reading them.

If you find any pointers how to trigger this issue easily please let us know.
Replication steps are often more than the half way to fix an issue.

Oh good point!
It might be then they would go to the minion to resuce, but then do not find a a path to a prison and drop it.
But to make this happen there must be a very long maze which must be more than two times longer than the maps diameter.

Which map is it, where is your prison and does it have space left?

Hello Rax,
can you add a bit more details what happened?
I am unsure what issue you describe exactly.
Can you make a screenshot or even better a video as well?