custom meta box conflict

Hi,

I created a meta box to link posts of a certain type to posts of an other type, following this description : https://wordpress.stackexchange.com/questions/85107/populating-meta-box-with-select-list-of-existing-posts-and-assigning-it-to-cust#answer-85281
I put this in a custom plugin.

It works well but I have a conflict with the plugin “The Events Calendar” : it prevents event dates to be saved. I don’t know how to solve this conflict…

I don’t use the meta box on event post types. Is there a way to ignore the functions in my custom plugin when on event edit page?
Or would you advise me to search for the solution elsewhere ?

Thanks in advance.
Lore