Make sure you have the latest version of the game.
If you got it from GOG, there is now a version 1.02
http://www.gog.com/forum/broken_sword_se...sion_102_pc_macThe tech support site at Revolution
http://www.revolution.co.uk/support/bs5/says this bug was fixed in version 1.01 :
Help! The game crashes when I try to interact with Adam/Fleur in the flower shop/when I try to combine items in the inventory
We have now fixed this bug and it is remedied in V1.01.
So it should also be fixed in version 1.02.
Check the site where you downloaded the game from.