Hello Rustam,
I did load your save game and was able to reproduce the issue.
The reason this was happening is that you own so many mana shrines,
that the cost for applying annex gets down to almost zero.
However someone decided to not remove mana and return false in this case,
so the Annex spell thought it can not perform, while it can indeed.
So this was a corner case happening with many mana shrines on spells with low mana cost.

This issue will be fixed next patch.
Thanks for reporting!

The log file contains logs of many multiplayer games, however finally something broke.
One of the reoccuring errors in the log we did fix internally already but there is a second one we need to look at.
However I do not yet see how they can be related to an empty lobby screen.
We need to investigate deeper.

This issue is fixed as early Unity 5.5 comes out of beta which will hopefully happen in a couple of months.
If they keep their plans we will have it fully fixed with Patch 1.5.

Just to give some notice: We are working on a new Patch which will be released in a couple of weeks, which should have this issue fixed.
The problem: It might not fix your existing save game, but it will make sure that future save games won't break like this.

We did made it faster again.

However when he gets knocked out there he will rot and after 60 seconds respawn.
So the problem should resolve itself after a short time.

Hello CMDR,
such issues are normally not caused by games itself but by an issue with the hardware configuration, which only occur when the system is under full load.
A shutdown either happens, when the PSU can not supply enough power for all the installed devices or when the cooling is not working to full extent, which can cause an emergency shutdown because of overheating.

When the PSU is too weak one can only get a better one or disable/remove power hungry devices.
Cooling issues are either caused by dusty fans not able to cool as good as usual or by overclocking the system while cooling is not strong enough.

WftO can be quite affording depending on how large maps you play for how long and how big you build.
Your rig looks like a real monster which should have no issues handling the game,
but if PSU or cooling is not strong enough it can run into issues even easier than with less powerful hardware.
It is also hard to compare with the mentioned games as you can go big or small in WftO.
However I have never heard of such problems with the campaign, which is not too heavy in terms of CPU/GPU load.

Did you look into Windows Event Viewer if there are any errors which explain the shut down?
(Type "eventvwr" in run/search bar, under "Windows Logs" -> "System" and "Application", look for red log entries at the exact time it did shut down)

Does it give any pointers?