Currently, it is not possible to give parameters to scripts which are executed during the UI.
We have an improvement CDS-42003
in our tracker to improve this (but it is not yet scheduled).
However, it is possible to pass arguments to scripts which are executed via the codesys command line interface, see the online help for a description.
Additionally, the script itsself can use system.ui methods to ask the user interactively for values like project names. I did attach a test script which shows the possible dialogs.
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