The previous interface utilized "Notes" which lets users insert notes/comments in a precise location of a book. The new interface has the same feature, with the same name and it works the same way. However, a note in the in the new interface looks a bit different than a note in the old version, as shown below. To re-create notes, we recommend you either make hand notes of the locations of notes you want to preserve, or use the Windows Snipping Tool and Microsoft's Cut/Copy/Paste commands to capture your precise note from the old interface and put it into the new interface.
In the previous version of Books24x7 notes looked like this:
In the current version of Skillsoft Books, the same note in the same location looks like this: