Reading problems with iBooks in High Sierra

Hello,

I've been having the following problems with iBooks in High Sierra:

(1) When attempting to click on the scroll bar when reading a book, the progress snaps back to the first page.

(2) The bookmark function does not work. When clicking on the arrow to view the list of previous bookmarks, iBooks hangs and requires a force quit.

(3) When reading a book, the pages will suddenly go blank, for either sections of the book, or the whole remainder of the book.

(4) When reading a book, iBooks uses up 100% of the processing power according to the activity monitor.

(5) If left in this state for too long, iBooks will hang the entire system and sometimes require a hard reset of the computer.

(6) This predominantly happens with "generated" epub books, such as those generated by the Internet Archive, or those generated by Pages.

Is there anything I can do to fix this problems? Any help would be appreciated. Thanks.