So what you want to do is invent a programming language, and make it work by parsing it then translating it to Perl. If the language is simple, that shouldn't be that hard to do.

However you want to make it not look like a programming language. And you want it to be capable. And you don't want to let your users know that they are actually programming. Oh, and you want to be able to extend the language easily.

That's a hard problem. And it is mostly a psychological one. What I'd suggest doing is a lot of whiteboarding. Write up samples of what people should write and what it would do. Go over it with users. When you have something mutually acceptable, then write a filter to turn that into Perl code. (Filter::Simple may help.)

You can then make it extensible by having some command in your new language that loads a Perl module that adds new functions. :-)