No matter how good you make it it will still suck because it uses GameMaker. GameMaker isn't intended for this sort of thing.
Yoyogames now supports the creation of utilities, and some damn good non-game creations have been made with the tool.
This is a mix of productive but fun "apps" including games. Game Maker does the job here, and if it was in C or in GML the end product wouldn't differ enough at this stage for me to want to learn a whole new language.
You have really admitted in that post that you don't care about the program, you just have bias towards Game Maker. Just because you don't like the language used to develop it doesn't mean it "sucks".
People who want to debate the tools used in the creation of the program probably aren't going to fit into the audience AfterBlock is aimed at. My choice of coding language does not effect the end user anyhow.