Re: Cursor patches

[H. Verbeet]

Another update.
  - The patches don't use INVALID_HANDLE_VALUE anymore (I was using
that in some of the other patches as well).
  - riff_find_chunk() compares DWORDs
  - Code using get_cursor_frame() now has some error handling, in case
the handle is invalid
  - Warnings should be fixed now, although I don't get the second one myself.