Application Configuration Items?

Did I see a class for application configuration ?
Saving configuration elements between application invocation?

We can’t know what you saw. Normally, these things are called preferences. There are classes available to save and read preferences. Please give more information when you mean something different.

I use

Application Data stuff installed at application first run (and checked at each run) ?

Something like what Xojo do with its local LR (and other stuff) ?

MBS Plugins come with an example for this:

Uses SQLiteDatabase and dictionary combined.

Maybe just pickle/unpickle a dictionary to a resource file?

That isn’t as easy as it sounds when you want to do dictionaries in dictionaries. Kem has code for serialising/deserialising if my memory doesn’t fail me. Name of Serialiser???