Are the settings synced and the Previews just slow updating. Previews need to be rendered after changing settings, you can let Lightroom do this on demand (which is what is happening) or you can use the Menu command to activate rendering.
I am not sure what you mean by using the menu command to activate rendering of the previews. The settings are not actually changing until I scroll through the previews and they change one by one. Even when I go to the develop mode and view the pictures in the grid view, they still are not changed. If I try and export the pictures for a slideshow or for a time-lapse sequence, the picture settings are not changed unless I have scrolled through the whole group of pictures and they change one by one. I am working on a time-lapse sequence with 1200 pictures. When I synced the pictures, the progress bar showed that the program went through and synced them all but the previews did not change. They don't ever change unless I can see them in the window, then they change one by one. I have a brand new very fast Mac with plenty of ram and SS hard drives. This process should go quickly. Any other thoughts?
In the Library Module, in the Library Dropdown Menu is the Render Previews section..... What are is your standard preview size set to currently??
Preview Size is set under Catalog settings and ought to be a size larger than the pixel width of your screen
Hope that helps...... Previews will not change until you need one larger than the Standard size or you go to the Develop module....unless you render them.
I am suddenly having sync problems - notably the exposure is way reduced and I don't see any other items sync. I cannot reach Adobe Lightroom by phone and I don't see this problem address either. This has been happening for a few weeks.
Similar sync issues - perhaps from a recent update?
Sorry I can't help you - just having similar problems.
Adobe - HELP!