Hi,
why dont you temporaryli also store the variables in the script you are running
let var_import_1 = $(var_export1);
and then in, on the button you fill the button with the external function 'set variable' var_export1 with the value var_import_1
see attached
What you also can do, is number the exported values and then fill the values in the script for the highest export number.
then in the button/script you will need to create a statement that adds value '1' to your export number after you reloaded it.
kind regards
Dick