For large assemblies, use the Open Files Selectively feature to improve performance.
This enables you to select which components to load, leaving others not downloaded and not visible. Make sure that "Open Files Selectively" is enabled in Solid Works Vault settings.
Not all Vault commands work with unloaded components; for example, the Property Write-Back command. These commands will not be available in the Vault browser context menu if any selected files do not exist in the local working folder.