Answering the most frequently asked question...
If there is one question I get asked more than any other, it's "will NESmaker be able to do _______". Most times, the question is broad, like "will NESmaker be able to make a game like Battletoads". Sometimes it's more specific, like "will NESmaker be able to use advanced sound chips". Because I routinely have to answer these questions across 10 different social media accounts AND here on KS, and the answer is generally the same, I thought I'd post it in one place for reference.
All NES games run on long strings of HEX values. An assembler takes 6502 Assembly Language and turns it into the hex values that the NES reads. One hex value might give a command, the other might be some sort of argument, another pair might be pointers to a new location in memory, and so on. When you play with hex editors, you're directly modifying that output hex data. When you write ASM code, you're seeing the data in a more logical way, which then "assembles" into the HEX values the NES needs to see.
Games created with NESmaker are no different. The difference is, we've developed a front end to do a lot of the 6502 ASM choices for you. What is assembling when you hit "test game" is still a hundred thousand lines of ASM code, turning it into hex values which a system or emulator can than properly interpret. The difference is, we are providing a drag and drop / wysiwyg style method of manipulating that code, rather than you having to write it in an code editor manually.
How does this answer the question? Well...simple. NESmaker can do whatever the code underneath can do, and could be made to do anything that a user updates the code to do. So when someone asks a quest like, "can NESmaker make a game like Battletoads?", it becomes very difficult to answer. What part of Battletoads are you referring to? Just being a beat-em-up style game? Sure. The parallax scrolling? Probably not with it's existing mapper, as that sort of thing generally requires a mapper that supports better frame timing, but if someone is super proficient in ASM and really understands frame counting (if you want a long look at this, take a look at this Mystic Searches update!), they could likely figure out a clever way to split the screen to get this effect. Are we talking about the depth of the graphics? Sure...if one is skilled enough at graphic creation. Are we talking about having pingponging levels, where some are vertical scrollers and some horizontal? Sort of, though mirroring is static with this mapper so you'd have to be clever. And so on, and so forth.
So questions like these are really hard to answer, because the code underneath coupled with how the user cleverly employs it through the tool is what determines what is possible. For instance, years ago when we just had a top down demo, someone asked if we could repurpose it to make a beat em up. We explained that it didn't really work like that. We turned our back, and about half hour later, he had what looked like a Double Dragon game, just by changing the perspective of graphics and disallowing graphical direction changes based on up and down pushes.
This is why the question is so hard to answer. The answer, really, is NESmaker can do whatever a mapper 30 game can do, which is pretty much whatever a standard NES game can do. However, more advanced tricks require more advanced usage, just like anything else. Once, I swear I had someone ask me something like, "Can I have it where, like, you have a boss, and he taunts you, and then he like goes up off the screen, and then, like, you have to hit a bunch of switches, and then the music and colors change, and then he appears and you have to fight him, but then he turns out to be an NPC, and then he gives you a key or something?" Those are the types of questions that are impossible to answer. The answer will always be "if you can concieve of a way to do it...but there won't be a single button you push called the "boss-taunts-flies-switches-musicChange-appear-fight-NPC-key" button in NESmaker. One would have to walk through the logic. What NESmaker is allowing a user to do is to be able to start conceiving it without having to write it all in ASM code, but rather a more intuitive front end interface.
Think about it like this - if someone was talking about word processing software like Microsoft word, the equivalent question might be "Can I make a script for an action movie like Terminator 2 with this?!". Which, of course, is really hard to answer. Sure, it can handle the formatting fine. But it's still up to the user to actually create a compelling script, understand dramatic timing, understand how to create evocative scene descriptions, character arcs, etc.
I hope this makes sense! If you ever feel compelled to ask "can NESmaker...", refer to this post for the best answer. :-)