Incompatibility between NextGEN Gallery and M.E. Calendar Lite

In several sites, using PHP 7.x and WP 5.x I cannot get working both M.E. Calendar Lite and NextGEN Gallery plugins. As soon as I activate NextGEN Gallery, ME’s events cannot be edited in any way, their edition screen shows an error. The existing events are still ther, but WP shows an error when you try to edit them. (“The editor has found an unexpected error.”)

I don’t know what’s the cause of this problem, but it would be nice to be able to have both plugins working in my sites.

There it goes a copy of the error thrown:

Error: An error occurred while running 'mapSelect': Cannot read property 'ngg_post_thumbnail' of undefined
The error may be correlated with this previous error:
TypeError: Cannot read property 'ngg_post_thumbnail' of undefined
    at https://fcylfwp.toools.es/wp-content/plugins/nextgen-gallery/products/photocrati_nextgen/modules/nextgen_block/static/build/post-thumbnail.min.js?ver=3.2.23:1:13830
    at Object.current (https://fcylfwp.toools.es/wp-includes/js/dist/data.min.js?ver=4.9.2:1:19491)
    at t (https://fcylfwp.toools.es/wp-includes/js/dist/data.min.js?ver=4.9.2:1:19116)
    at https://fcylfwp.toools.es/wp-includes/js/dist/data.min.js?ver=4.9.2:1:19227
    at Vb (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:104:431)
    at Ti (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:148:85)
    at unstable_runWithPriority (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react.min.js?ver=16.9.0:26:340)
    at Ma (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:52:280)
    at Ia (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:140:407)
    at ze (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:118:14)

Original stack trace:
    at Tt (https://fcylfwp.toools.es/wp-includes/js/dist/data.min.js?ver=4.9.2:1:18925)
    at https://fcylfwp.toools.es/wp-includes/js/dist/data.min.js?ver=4.9.2:1:19466
    at je (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:78:476)
    at qe (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:89:115)
    at ph (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:216:489)
    at lh (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:126:409)
    at O (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:121:71)
    at ze (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:118:14)
    at https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.9.0:53:49
    at unstable_runWithPriority (https://fcylfwp.toools.es/wp-includes/js/dist/vendor/react.min.js?ver=16.9.0:26:340)

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