Transferred files are being saved in the Downloads folder
When you download (transfer) a book over the network, it will be saved in the Downloads folder inside your home folder.
To turn this behavior off, change the following setting.
(It will then be saved to the currently open folder.)
ComicGlass General Settings
└ Book Transfer
└ Save to Downloads folder: set to Off
Info:
This specification was implemented to comply with Apple's review guidelines.
(Items that can be re-downloaded must not be included in iCloud backups.)