Ok I gave it another go on the download version.
I still found it way too hard. It's also annoying have to wait through the sample each time on restart. Would be nice to be able to click past that like for the text.
I didn't hear a sound played when I hit the keys. If there were sounds for each of the 4 directions - e.g. snare, kick, hi-hat and toms then it would feel a lot more like playing along to the track. This should increase the immersion too.
As it it now, the buttons change position, the same button is synched sometime with kick drum, sometimes with snare - it's too much change all at once.
Maybe keep the 4 buttons in the same place on the screen and oriented in the same 4 cardinal points (up/down/left/right) at least on the earlier levels.
You might have to remix your track though.
Now what would be really interesting would be if you used more theme appropriate music such as the trolololol song or a Russian folk song from the time.