WoW's list of resolutions comes from your video driver. WoW will filter out various resolutions but should always include whatever the current desktop resolution is. The setting from Config.WTF is NOT automatically added to the list, so the drop-down box will not always show the right setting.

Side note on this topic, when Inner Space 1.11 comes out (in the next week or two) there will also be a minor update to ISBoxer 37. This update will add custom resolutions, for all games, synced to your Window Layout. Most games will filter out most of the resolutions IS adds, but they will pretty much all include the actual resolution used by your Window Layout.

In other words, soon ISBoxer users will be immune to the issues described on this thread. The drop down will show the correct resolution selected, and Tukui will work correctly. Huzzah!

p.s. this is already done and working. If any ISBoxer users are interested in trying this out, stop by the ISBoxer Chat Room and I'll hook you up