Hey, thanks for trying the demo.
So let's see here..
Music will be updated at some point, not sure when but likely closer to when the game is finished.
I can see how some letters could be hard to read with the game font, but not really how it would be completely unreadable. That being said however, I have plans for adding an option to use a standard font like Arial or the like in the future.
As for the control issues, never heard of or seen any of these. The control scheme you're talking about (down arrow to confirm etc) doesn't exist so something else is wrong here and I'd like to clarify that I'm not saying I don't believe you, this control scheme should not exist though (unless it's custom made). But this did make me realize one thing though: I should add restrictions for certain buttons so that you can't bind for example - "down arrow" to "confirm.
I haven't tested the game with JoyToKey so I will add that to the list in case JoyToKey does something weird to the game. I do not have a SNES controller either so this one I can't really test.
You should be able to aim diagonally up when standing still but as something seems wrong I understand it could be broken.
The game should also not swap controls around unless you bind them or change control scheme so no clue what could be going on here.
And finally, not sure what you mean about auto detection? If you mean controller detection there is an option for that called "Controller Enabled". (should probably rename this to controller detection)
Unless your computer can't compile or handle shaders for whatever reason then you might be able to play with those graphical things enabled. Using the "Frame Skip" option in the "Display" menu should help a lot with framerate issues, this does render the game in 30fps instead of 60fps however if this is something you do not desire. I have tried to optimize it to run it on weaker machines, still lots to do of course, but I can run it pretty decently on my very low end laptop using said frame skip option and low/medium graphics. This is where the minimum requirements listed on the game page comes from. This is on Windows however so if you're talking about Linux then I can't do as thorough testing since I only have a virtual machine available for that at this moment.
The character speed up thing is probably not going to change, I want the character to feel slower and honestly, a little bit clunky, not too much though of course.
The reason for having to go to the map and then pressing a button for the options menu is exactly that, buttons, there's not enough of them, I'm speaking in terms of using a controller since of course there are enough buttons on a keyboard, but if you're only using a controller then this seemed like the best way to do it ie: using less buttons. But if you have another idea, please let me know. Also, not sure what to do different about the efficiency part as this is just the same menu as the title screen menu, again, speaking in terms of using a controller so there's no mouse or such available here.
Sorry that there were too many issues for you to enjoy the game, I try to make it as enjoyable as possible for everyone but sometimes it just does not work.
Anyway, I tried to answer all the issues, if you have any suggestions and such please feel free to tell me.
(also, sorry for the giant reply) ;)