set up a field (dynamic list) with the custom screen plugin

Hello

you can create value lists with the plugin. I invite you to read the manual of the latter available via the store to check that it corresponds to your needs

If what you need are dependant lists, no it does not exist in Screen Customisation plugin, and it is not in the roadmap of the plugin.
It could be an improvement of the plugin but would require to change structure of Lists management in the plugin.
The major, being possibility to defined the dependency in classes.

For instance, you create custom List Country. OK.
Then you create List Town, and need to specify that Town depends on Country.
This way, when you defined an item of List Town, you have to specify its Country.
Finaly, we would have to change general framework so that it can dynamically update list of field idTown when value is changed in list for field idCountry (auto detecting the dependency).

I'll record this in the roadmap, but sure it will be with low priority.
If you really need it, maybe you can consider sponsoring it developement (contact us if this interest you)