Thank you very much, Olaf, for the beautiful layout.
I have found all assets, except some, made by you: <kuid:386322:704>,<kuid:386322:703>,<kuid:386322:967>,<kuid:386322:705>,<kuid:386322:965>,<kuid:386322:964>,<kuid:386322:966>,<kuid2:386322:678:127>,<kuid:386322:3150>
Any help is very appreciated. Thank you in advance.
The reason that is happening is because the spline point is too far away from where the tracks actually diverge and the tracks going left, actually go slightly right first (although you can't actually see it).
The easiest fix is to move the spline point closer to the actual turnout. Alternatively, if you straighten the section of track which is the siding, I think that should fix it too.