This is good, Amitai ! At last we can have some Medtner on the site.
First of all, sound quality is perfectly fine. I did not hear any extraneous noises, except from some audible page turns (you may want to take care of those - if one occurs nicely between phrases it is easy to cut it out with an editor). Obviously this piece is too long to use photocopies taped together

I find that baby grand a bit feeble in the bass department - did you have the lid open or closed ? Maybe your Edirol positioning and equalizer setting (if you use any) can help too. I think Medtner needs to sound a bit deeper and darker than it does here.
Technically, your playing of this piece is consummate. Apart from one little stumble in the finale, I could not detact any slips or read errors worth mentioning, and I know this piece intimately (I have been thinking about recording some Medtner, and this one would have been a candidate). This may be an easy one by Medtner standards, but it is still quite a handful and you do a great job.
On interpretation, I have some observations which may be purely personal. I think you underplay the drama of this piece by taking it a mite too slowly and politely. Especially in the stormy middle section I miss the power, urgency, and dark undercurrent. Where are Medtner's
minaccioso and
tenebroso ? Not sure whether he uses these directives here, though ... would have to check the score. One other thing that does not help is your tendency to slow down and make pauses between phrases. A good thing in itself but it must not lead to breaking up the music in disjointed parts (as I felt happens a couple of times in the finale). I fear that listeners not (yet) attuned to Medtner's sometimes longwinded music may well lose interest somewhere during this very long piece.
I understand why you take a very lyrical view of this piece - after all it is wistful and nostalgic most of the time. So I am not suggesting that your interpretation is not right - only that perhaps more urgency and drama is needed in places. It is by all standards a very good rendition which I'll be happy to put up the site. Can you provide me bio information and (optionally) a photo ?
Also, I have just made up a new rule .... The first one to introduce a new composer on the site gets to write the composer bio

But you don't
have to ... it's just I am getting a bit fed up with all this bio researching/writing for the site.