Creating a default Custom Post Template that a Theme can override

I’m in the midst of building a WordPress Plugin that adds a custom post type, for which I’d like to include a default template to display. Essentially, this is an event management plugin, and the custom post type is for the Events. There’s a handful of custom meta fields, as well as a child post type (Performances), so without a default template to display them, using it would be pretty unfriendly. But I would like theme designers to be able to create their own templates for these post types if desired.

How to create a flexible abstraction for WP_Query?

My question is about php but it involves wordpress as i am creating a plugin. The case is that i have 5 questions, each question have 6 choices and one choice to choose from each. Now the person would select any choice from each or just few. I have created the if condition that is now making me mad, as it has gone too long and will do further, like nearly 100 combination will be made. I wouldn’t want that, i know there is a way of multidimensional array but in am not a plugin or php expert for wordpress. so if anyone can sort it for me.

Altering the appearance of custom taxonomy inputs

I’m working on a site that will make use of a few custom taxonomies (for custom post types). I’ve chosen to make some of the taxonomies hierarchical because the method of inputting values (checking boxes) is more desirable for this site than the free-form input of non-hierarchical taxonomies. However, what I would really like is to be able to use radio button inputs instead of check boxes. Additionally, I’d like to remove the dropdown that is used to choose the parent item in the taxonomy.
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