Wouldn't it lag? I've heard that loading big strings using that action causes freezing
What is "big" for you? because, 100 lines of plain text is nothing.
Lag comes into play when the file is too heavy (let's say bigger than 1mb. I've just created a file with 10.000 characters and it sized 11 kb) but you can always have a loading bar
There is no problem doing that, don't worry. Is the way to go. It is common to have one or more json for configuration and one xml for text (for localization purposes).
In any case, always have a plan b inside C2 "code" for any problem loading your files, using "AJAX - On error". I call that "default values".
> 2. I don't understand your problem. Better solution for what?
I have to use AJAX plus external files just to have arrays loaded with parameters, as reading directly from AJAX.lastdata would mean loading a file each time (not instant). A better way of handling this, is what I meant.
A "better way" is not to load those values from external files, but internal vars/arrays/dictionaries. You can have a configuration event sheet where you'll edit your values directly in C2. This way you will not need json, xml, or any other format but C2 conditions or actions.
The answer you are looking for is: "it is internal or external", there is no other way.