Crashing To Desktop after ~10 minutes of game

[Sanofi]

The problem is, that Civ4 keeps crashing to desktop always after about 10 minutes of game. The game is patched to 1.52, the same problem was with all the previous versions too. Tried every remedy suggested in tech support - no luck.
ThemeParseLog.txt says the following

[Dec 29, 2005 - 00:15:38] Messages while processing 'Resource/Themes/Civ4.thm'

Error : Decl - ('Civ4Theme_Common.thm', Ln:401, Col:13) Assignment source propertyId 'SF_CtrlTheme_Civ4_Control_Font_Size3_Italic' not found
Error : Decl - ('Civ4Theme_Common.thm', Ln:402, Col:13) Assignment source propertyId 'SF_CtrlTheme_Civ4_Control_Font_Size3_BoldItalic' not found
Error : Decl - ('Civ4Theme_Common.thm', Ln:408, Col:13) Assignment source propertyId 'SF_CtrlTheme_Civ4_Control_Font_Size1_Bold' not found
Error : Decl - ('Civ4Theme_Window.thm', Ln:3048, Col:9) Assignment source propertyId 'SF_CtrlTheme_Civ4_Control_Font_Size1_Bold' not found

My system : AMD Turion 1,8 512ram ATI X700 128mb, Win XP SP2

Help me please, I am getting desperate already !