Daniele Grillo (grydan.it) has brought to my attention a bug related to HCL Domino Designer 12.0.2 64Bit.
If the NotesUIWorkspace.Prompt method is used in LotusScript with certain types, and the script is created in Domino Designer 12.0.2 64Bit, the function calls do not work in HCL Notes 12.0.2 32bit.
In detail these are the types
The issue has been confirmed by HCL Support and is tracked under SPR# PSHECLNFST.
I have created a small database that you can use to test the behavior yourself.