Have any question?

Of course! The game contains tutorials. You can also change the difficulty on the settings.

Unzip the downloaded file, and open PataRoad.exe.
Note that the unzipped game size is 1GB, so check if you have enough free space.

It's known issue. Well, I tried many things, but it still does.
I can't fix it, but it's very low chance, so shouldn't affect to the game playing.

Maybe?
Well, nobody blocks reporting, but the fixing requires "next version", so cannot be fixed so fast.
Also, if you can't reproduce the steps, there is high chance of that the bug cannot be fixed.
Another note: if it's a bug, if it doesn't affect much gameplay, it'll be fixed slowly or won't fixed.
Every bug has priority!
And Some of the things you thought it's bug, can be actually "feature/by design" ;)

I tried to fix music, but it's still very hard work.
So currnetly there is no plan to update music.
Still, if you play easy/normal or with metronome, there shoulnd be no problem.
See also 0.81-1 changelog.

About half of the game progress is easy, if player can play very well. Try difficult play mode - better reward is bonus!
If the game is too difficult, first, change your strategy. Try different classes or/and summoning boss.
If characters die easily, make your army stronger. Develop Rarepons and/or equipments. Check the tips again.
I tried going through all levels in legit way, so I'm sure that there is no impossible level.

Not right now :(
But if you want, you can make the game guide, and also I can make guide on demand.

First, I'm not an artist. Second, it's focused on functionality.
Third, after all, it's not original game. So I can do nothing with it anymore.

It depends. If people don't play the game or there is nothing to fix, I have no reason to update.
Since the patch or update checking system isn't supported at all, if there is any future update, it won't be performed frequently.