Glad I stumbled upon this jam. This game is absolutely fantastic, absolutely going to keep an eye out for more updates on this one in the future. I have no knowledge of any prior versions but my issues are extremely minor. With this kind of game, the absolute most important thing is that the game feels satisfying and this game absolutely nails it-- The movement, the shooting, the explosions. All wonderful. Really fun variety with the weapons and scoring system too.
My only issues are aesthetic (and one mechanical)-- I found myself often losing track of my player character because the main mech has very drab colors that blend in with the environment-- Particularly in the first map (it's not as big of an issue with the enemies because they get outlined in red). In mecha anime the main robot usually has very flashy colors, like the Gundam's white and blue, and the tone in this game doesn't seem to be super gritty, so I don't see why the main robot can't have colors that make it stand out more.
On that note, I'm not sure if the lack of music during stages is meant to be just a demo thing or an intentional choice. If it's an intentional choice I respect it, but I do think some beats would elevate the experience. My final nitpick is that, unless I missed something, I didn't really notice any kind of progress indicator for how close you are to completing a mission.
I understand something like an enemy count might feel tacky and "too videogamey", but I think it would make things more exciting if you actually felt how close you were to the end at any given time-- Could be something as simple as one of those Pilot cut-ins making a comment like "Just a bit more!" or something once you're near the end.
Like I said at the beginning, this game is one I'm going to keep an eye out and root for going forward. Especially the fact that it's in Game Maker-- Studio 1, too?? Astonishing. Keep up the good work!