Hi Milo,
Make sure that there is an updated version of the controls you are trying to update on the pre-release site. If you are running Live Update it should find everything that is on pre-release, but some of the controls you have installed might be newer than the controls on pre-release.
If you see something newer on pre-release that isn't getting picked up by Live Update, please get in touch with the support team and let them know. There aren't any known issues but there might be something strange happening.
Thanks!