This bug occured in 1.91.2, but in my last version (i think 1.90.x) it still worked correctly:
I use Windows XP SP2 and have two network printers. When I want to print something I am able to select the approbiate printer for the task (b/w or color). Then I can change settings for that printer too.
It used to work like this in XnView too, but not anymore: If I select printer 2 and then select settings the new dialog windows opens with the settings of printer 1. Of course I can switch to printer 2 then, but at first I didn't noticed this so this is one cause of possible errors. The big BUG is that even if had selected printer 2 for printing the print job is always done on printer 1.

The dialog for the printer selection seems to be broken; it doesn't notice the new selection (and this behaviour is quit similar to the unit (cm or inch) selector bug I reported some days ago).