I have made a WinBoard binary of 4.5.0 as it should have been, and incorporated it in an installer package. It can be downloaded from
http://hgm.nubati.net/WinBoard-4.5.0.exe .
Barring a major foul-up, this will be the package through which WinBoard 4.5.0 will be distributed. I hope some of you can test if everything works as it should. If I get no complaints today or tomorrow, I will create an official download link for it in WinBoard forum.
Changes compared to the 4.4.x downloads are that I threw out some of the variant engines, leaving only Pulsar and Fairy-Max (which together already cover a very wide range of variants), and added a Shogi section with one engine. There now also is an "internationalization" section with Spanish, Italian and German language files.
Note that the HTML help is not entirely up to date, and still describes the old menu organization. I did not want to delay the release just because of that, as it isnot clear when this will be fixed.