I’m running amd64 and am not having this problem. I always install oxygen-mouse-cursors-extra and then use Oxygen Red. I set this in both places: in System Settings → Workspace Appearance → Cursor Theme, and by setting it through the alternatives system:
sudo update-alternatives --config x-cursor-theme
This always works, and stays stable. And, I might say, a red mouse cursor is much harder to lose on the screen than a black or white one.
I use my favourite GlassyRainbow cursor theme in x64 via Get New Theme… in System Settings > Workspace Appearance > Cursor Theme It always works immediately and stays current in KDE without further setting, however in Gnome etc I have to manually edit the index.theme (as root user) in /usr/share/icons/default.
for example: