Ok, finally my script works
For some reason, when I wrote :
dt0:my_column << set property ("Map Role", Map Role (Shape Name Use (path, "my_column" ) ) ;
It wouldn't transfer the string contained in the variable path into the column property. It still wouldn't work when I tried to use Eval(path) and other workarounds. I'm guessing JSL doesn't support evaluating variables Inside this message.
So here is the workaround I found :
My_expression = Eval Expr ( dt0:my_column << set property ("Map Role", Map Role (Shape Name Use (Expr(path), "my_column" ) ) );
Eval (My_expression);
And this finally does the trick!
The step to convert the path from posix to Windows was not necesary in the end, as the column property accepts both formats.
~~Bob~~