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.
is not very specific.but it did not work
Did you enable Joomla error reporting?I did not get any error message
It's only one zip file. The zip is about 7.5MB so make sure your server upload limit is big enough or use Joomla's "Install from Directory".the files