Using KOReader from Calibre Sync

Hello:

I'm trying to use KOReader with Calibre Sync library manager (CS further down) on my Galaxy A54 Android 14 smartphone.

I'm able to acces and manage a local drive copy of my Calibre library using CS: it correctly maps all of the available metadata.

However, CS won't open for reading ebooks on mobi or epub files using the installed KOReader app.

Any ideas or recommendations?

Awaiting your kind reply,