You might want to give the alternative readers a try:
a guide to installing them so you can launch them from within the Kobo software.
I no longer use the Kobo software (Nickel) myself I prefer the simpler
Kobo Start Menu
And - I hide my ebooks from Nickel's processing and database:
For those who are trying the Alternate readers because you prefer a "File Manager" approach over the corruptible database book management approach that Kobo uses; you can easily hide your ebook files from Kobo's database and processing. All that is neccessary is to place the files and folders of your ebook collection in a hidden directory/folder. For a Linux device "hidden" files folders or directories are those that are named with a dot/period before the name ( like .kobo or perhaps for this use .library ) To make such a folder/directory using Windows Explorer you just name the folder with a dot/period both before and after the name (like this ".Library.") the trailing dot/period will disappear leaving the "hidden" name you want (like ".Library")
It can also be done using the commandline command MD.
[I have all my ebook files on my external uSD card within a "hidden" directory, ~7000.]
Luck;
Ken