I know it was present in earlier releases (e.g. see next three links) but not sure if it was thought fixed?

https://forums.elementalgame.com/446854 (v 1.3)

https://forums.elementalgame.com/449846 (v 1.4 - see further down the conversation)

https://forums.elementalgame.com/450033/page/1/#3416861 (v1.4)

 

Couldn't find anything else on the forums since v1.5, although I noticed a note was made of changes to the Daxus quest in the v 1.5 release notes.  Think this addressed missing weapons rather than the crash though? 

 

Tried a little troubleshooting.  My save game captures the state of things immediately before moving onto the quest tile.  The stack has room for one more, and Daxus can be seen added to the pile before it crashes.  Inspired by one of the above discussions, I also tried it with a full stack so Draxus was unable to join the fight (there's a mage with 6 move a small distance north that can easily be brought to the party) and... it doesn't crash!  Seems the issue only relates to Daxus joining at the last minute.

 

Hope this helps track down the bug...