http://bugs.winehq.org/show_bug.cgi?id=7801
--- Comment #1 from Marcel Hasler mahasler@gmail.com 2008-02-10 15:15:24 --- This seems to be the cause of the problem:
fixme:d3d_surface:IWineD3DSurfaceImpl_LoadTexture (0x19870c0) Operation not supported for scratch textures fixme:d3d:stretch_rect_fbo >>>>>>>>>>>>>>>>> GL_INVALID_FRAMEBUFFER_OPERATION_EXT (0x506) from glBlitFramebuffer() @ device.c / 6343
This happens every time you ESC out of the game back to the menu.
Commenting out the "if (This->resource.pool == WINED3DPOOL_SCRATCH)" test in IWineD3DSurfaceImpl_LoadTexture() in dlls/wined3d/surface.c fixes this and makes the screenshots work.
Apparently more games are affected by this bug, e.g. "Touhou Bunkacho" (see the comments at AppDB).