For running J!5.1 you must https://fabrikar.com/forums/index.php?wiki/update-from-github/ or include the new file manually https://fabrikar.com/forums/index.php?threads/joomla-5-1-and-fabrik-cannot-find-files-error.54473/post-285151 See also Announcements
Please see our announcement here.
Like so often, this is all very generic, particularly the term "report". Some call a table list a report and are happy with it, others mean some fancy infographics and what not else. So, without good and detailed specs any response here can be very right or very wrong = a lottery.