Updating my Shape5 sites to Wordpress 5.5.3 created problems with some plug ins, seems to be mainly the

sacontractors.co.za

WordPress caught an error with your theme, Shape5 Regan Tech
Error Details
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An error of type E_COMPILE_ERROR was caused in line 80 of the file /usr/www/users/saconpxbfz/wp-content/themes/s5_regan_tech/vertex/theme-admin.php. Error message: require(): Failed opening required 'admin/elements/vertex.php' (include_path='.:/usr/share/php')

mrsh.co.za:

WordPress caught an error with your theme, Shape5 Modern Flavor
Error Details
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An error of type E_COMPILE_ERROR was caused in line 21 of the file /usr/www/users/mrshcqpvth/wp-content/themes/s5_modern_flavor/vertex/theme-admin.php. Error message: require(): Failed opening required 'includes/classes/loader.php' (include_path='.:/usr/share/php')

lifestylebuilders.co.za:

WordPress caught an error with your theme, Shape5 Business Line
Error Details
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An error of type E_COMPILE_ERROR was caused in line 21 of the file /usr/www/users/lifesz/wp-content/themes/s5_business_line/vertex/theme-admin.php. Error message: require(): Failed opening required 'includes/classes/loader.php' (include_path='.:/usr/share/php')

mhbconstruction:
Custom 3 and Custom 4 widget content doesn't show unless I right click and Inspect. On reload the content disappear again. I have reverted to the older version

WordPress caught an error with your theme, Shape5 Spectrum
Error Details
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An error of type E_COMPILE_ERROR was caused in line 21 of the file /usr/www/users/mhbcomssbg/wp-content/themes/s5_spectrum/vertex/theme-admin.php. Error message: require(): Failed opening required 'includes/classes/loader.php' (include_path='.:/usr/share/php')