Try going into Serato's Setup>Library and click the box next to "Protect Library" before shutting down Serato. In order to reorganize your crates again when you reopen serato just unclick that box and you will again be able to reorder your crates. Refer: five nights at freddy's fivenightsat-freddys.com demo online

Before turning off Serato, you can try protecting your library by selecting Setup>Library and then clicking the "Protect Library" checkbox. If you want to be able to rearrange your crates when you reopen Serato, you'll need to deselect that box.
fivenightsatfreddy.org