Unknown Unit Type : Hammer of Thursagan, Underlevels

[tonyg_wesnoth]

Wesnoth 1.5.0 playing Hammer of Thursagan on Easy.
On scenario : The Underlevels.
Have opened THE door and on End Turn I get :
Error while Playing the game : game_error : Unknown Unit Type.
Tried upgrading to 1.5.2 and reloading the saved game but same problem.
Thanks
P.S. I will post in the campaign thread as well.
WinXp Sp2, 2700+ with 7600GT and 1Gig RAM.
P.P.S Have read this http://www.wesnoth.org/forum/viewtopic.php?f=4&t=20144
but have no idea what stderr is or how to run with --log-debug=all
I tried to search on how to set it but the search engine only seemed to allow me one search every 5-10 mins. I did add -log-debug=all to the icon exe properties but couldn't find any additional output.

[AI]

Upgrade to 1.5.2 and see if it still occurs.

If you don't want to be bothered by bugs, use the stable line instead, of which the latest version is 1.4.4.

[tonyg_wesnoth]

I tried 1.5.2 but using the same Save Game and the problem still occurs. It took a LONG time to get to the failure point so I am not too interested in starting again with pure 1.5.2 I appreciate what you mean about using the stable version. However, as I used the latest version and got a bug, I thought it worth reporting it.

[Mist]

This bug is fixed in 1.5.2, but requires you at least to use 'start of scenario' save to benefit from the fix. Using a bugged save with a fixed version still results in a bugged behaviour.

[tonyg_wesnoth]

Ok Mist. Thanks for the info.