Problems with 'aviaAssetManager->generate_file' after update to Enfold 4.2.5

Recently updated Enfold via dashboard. Unfortunately site stopped working.
Found thread with recommendation to delete enfold and reinstall it from scratch.
Didn’t help

Error in logs:

php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "NOTICE: PHP message: PHP Fatal error:  Uncaught Error: Cannot use object of type WP_Error as array in /var/www/app/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/asset-manager.class.php:265"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "Stack trace:"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#0 /var/www/app/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/asset-manager.class.php(99): aviaAssetManager->generate_file('css', Array, Object(WP_Styles))"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#1 /var/www/app/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/asset-manager.class.php(65): aviaAssetManager->merge('css', 'avia-merged-sty...')"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#2 /var/www/app/wp-includes/class-wp-hook.php(286): aviaAssetManager->try_minifying_scripts('')"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#3 /var/www/app/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array)"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#4 /var/www/app/wp-includes/plugin.php(453): WP_Hook->do_action(Array)"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#5 /var/www/app/wp-includes/script-loader.php(1435): do_action('wp_enqueue_scri...')"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#6 /var/www/app/wp-includes/class-wp-hook.php(286): wp_enqueue_scripts('')"
php_1        | [05-Mar-2018 08:33:41] WARNING: [pool www] child 6 said into stderr: "#7 /var/www/app/wp-..."

server running php 7.1