Repro Steps
1) Get 2 Urkans
2) Open the training menu

3) Select the ability that those Urkans share

4) Close the Urkan menu without buying that ability

5) Re-open the Urkan menu

Observed Behaviour

When the menu is re-opened, the cost of the training will show 999 Dust. Also, the menu will stop responding entirely, so you can't close the menu. If you get invited to a new game, the menu is still open (overlayed above the lobby screen). The only thing that gets rid of the menu is restarting Endless Legend. Also, this bug is persistent through saves, so if you ever do this then that game is corrupted and virtually unplayable.

Mykara - Turn 108.sav

Same issue has struck me this morning.   It's so annoying.

Thanks for the report Mohsar. We'll take a look :)

I have the exact same problem. Thanks for looking into it. 

Same problem here.  Thanks for reporting and thanks for looking into it.  Hoping to be able to continue Mykara quest soon.  I'm half tempted to let my beasties go free so the other empires will recapture them and train them for me. :P

I've found a workaround for this, which involves changing your saved game file in a text editor.  Tread carefully, but perform the following steps to regain access to the Urkan Training Screen:

You'll need a text editor, and comfort with modifying XML files.  I've tried to make these instructions as clear as possible, and please please remember to work with a copy of your newest save, and never overwrite your newest save.  Being safe with this is pretty low risk, but it may take a bit of work or a few tries to make this work if you aren't used to working with XML.

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1.    Find your saved game.  In Windows, it’s in your Documents folder: Endless Legend\Save Files\ (and \Cloud if it’s a cloud save).  Copy this save to another directory.  You don’t want to tinker with your original file!

2.    Change the file type of the copy of your save to ".zip", because a save file is really a zip file in disguise. (You may need to turn on file extensions in your file explorer, if you don’t see them)

3.    Open the zip file and locate Game.xml and GameSaveDescriptor.xml.  Copy these files out of the zip file and into a working directory (in some situations, bad things can happen when you modify text inside of a zip file, and it's slower do edit it in a zip anyways)

4.    Open Game.xml.  IIt might be very large – mine was over 10MB – and it may take a while to load.

Skip to the very bottom of the file.  You can use Ctrl+End to do this in Notepad and Notepad++.  You’ll find a section called <Ancillary AssemblyQualifiedName="KaijuTechsManager" …>.  This is where Urkan training research is held.  It may not surprise some people that the working name for Urkan was Kaiju. :)

The bug exists when the player has Urkan Training Research in progress, so we make the bug disappear by deleting our research in progress.  You’re likely EmpireIndex=0 (the first player) so find the XML block for EmpireIndex=0.

First, change <Researches Count="1"> to <Researches Count="0">

Then delete the entire <Construction> block. Save the file.

5.    Next, open GameSaveDescriptor.xml and find “Title” at the end of the screen.  Change the save game to something that tells you this save is modded.  I used “Mykara - Turn 184 Modded” (this is so you can easily identify it in your save game list)

6.    Copy Game.xml and GameSaveDescriptor.xml into the Endless Legend folder of the zip file you have from step 1-3.

7.    Rename the zip file back to a .sav file, and with a unique name.  Like with the title, I named my  file “Mykara - Turn 184 Modded.sav”.

8.    Copy this file back to your Endless Legend saved game directory.  WARNING: Don’t replace your existing save! The .sav file you’re working on should have a new name!

9.    Run Endless Legend.  You should see your normal saved game and your modified one (I see "Mykara - Turn 184" and "Mykara - Turn 184 Modded".  Open your Modded game, and you should be able to access the research screen again.

NOTE: Just because your saved game has been fixed doesn't mean it can't break again.  Be sure to never Cancel out of the Urkan Training screen with research selected.

I hope this helps!