When creating a package, a potential error is:
Failed to create package: Preferences results in too many Ids, Resultant IDs can't be blank
Explanation
TitleLeaf can’t create a package with that many assets in it. Most often it’s because the file would be too large or it would take too long to create. The limit itself depends on your specific TitleLeaf instance, a setting named “Package Item Limit” (Admin > Management > Settings > Package).
Solution
Break your package into multiple, smaller packages. For example, instead of trying to package 3 years of ebooks, create packages for each individual year (ie, 3 smaller packages).
As a rule of thumb, we recommend packaging no more than a year of assets at a time. This recommendation ultimately depends on the number of titles your company create per year.