You probably already discovered what the issue is back in 2005. However, googling for the same issue in 2023 brought me here. For anyone else having the problem, you need to also set the LBS_HASSTRINGS state for the ownerdrawn listbox.

What is the point of putting the extra effort into making a nice general implementation of a fairly simple algorithm, which would save a few hours of development time for many developers, and then restricting the number of developers that can benefit from it? That seems very inefficient to me.

I was in need of an implementation of the Sutherland-Hodgeman polygon clipping routine. I've found two good looking implementations on the web, however, both are under the GNU-GPL, which makes them completely useless to me, and I'm sure a lot of other small commercial developers working with closed source. Why such a restriction on an implementation of a bunch of old algorithms? Especially when they're simple enough that any one can implement them. These works could be helping save time and effort for many developers. Instead they're restricted to the "club" of developers that have the luxury of developing in open source. Anyway, I ended up implementing my own version of that clipping algorithm. To all developers that feel the need to restrict who can use their code, thanks for nothing.

Well in the short time that we were using 64-bit Windows, Visual Studio 2005 seemed to work well enough. (Our problem was with the WinCE Platform Builder environment...)

Make sure *all* your development tools will work on 64 Windows. Not all of ours did and we had to switch back.