No, I tried to find out a while ago but with no success. Even the date of the recording gives no clue because it was made after Zaborov's death if I remember correctly. Likewise, it is difficult to compile even some basic facts about Zaborov's life and work. The liner notes of the Svetlanov box just mention "Grigory Zaborov, a composer, violinist and concertmaster of the USSR Bolshoi Theatre", and that's basically already all we know about him.

Must be Evgeny Stikhin (* 1932). He does have an article in the Russian Wikipedia:
https://ru.wikipedia.org/wiki/Стихин,_Евгений_Михайлович
according to which his piano concerto was his graduation piece at conservatory. A lot of his works, including his piano concerto, can be found here:
https://classical-music-online.net/en/composer/Stikhin/2181

Yes, certainly:
https://www.jpc.de/jpcng/classic/detail/-/art/anthology-of-russian-symphonic-music-vol-1/hnum/6654165

Actually, there was even a Vol. 3 (shorter and devoted to vocal symphonic music):
https://www.amazon.de/Anthologie-Russischer-Musik-State-Academic/dp/B079B8RHMB

P.S. As you can see in Mike Herman's discography which Gabriel linked to above, Zaborov lived from 1929 to 1985.

No, you are wrong, it's all completely right. I also have Parsadanian's Symphony No. 1 and it's a different work (including a solo soprano, for instance). Svetlanov did record Parsadanian's Symphonies Nos. 1&2 but they are not included in the Melodiya box. However, Parsadanian did write a piece called "David of Sassoun", Epic Poem for Orchestra (1949), which is the one recorded here. And the symphony is by Zaborov.

No doubt the title does not fit. I guess the persons in charge either did not know much about classical music or did not have a closer look at the collection or both options hold true.

In fact, there was a huge Balkanton Vladigerov edition on LP, and my guess is that these are the recordings Capriccio is about to bring out on CD. This is actually quite a surprise, but a very pleasant one, since Vladigerov is of course a very fine composer and there is a lot of very interesting stuff to be discovered.

I heard about this new release a while ago, and I think I read that the recordings which are ready for release should be the old Balkanton recordings from the 1970s (or so). If this is true then these are fine news, since these are performances of a high standard (in case of the Fifth Concerto, the pianist should be the composer himself) and probably much more than just a substitute for a newer recording.

The link is as follows:
https://archive.org/details/pogonyi-cds

Maybe one addition as for what can be found in this collection. Most of the stuff is either from broadcasts or from live performances since Miklos mostly focused on non-commercial recording in his late years. There are some LP transfers here and there but not on a larger scale.

I should add that what you found on archive.org is a part of the huge collection of the legendary Miklos Pogonyi (more or less the stuff he had digitized – there was even more on tape). Miklos's collection was truly vast. In his last years, I exchanged a good deal of music with him, which was always fun. At that point, he was already very ill, and in March 2017, he passed away aged 71. In his last years, he was pretty much worried about what to do with his collection. Finally, donating it to archive.org has obviously been a very good idea.

I also bought my copy a while ago – you might remember that we already briefly mentioned (and discussed) this CD in April:
http://artmusic.smfforfree.com/index.php/topic,7038.0.html

As for the music itself, I am happy to have these rarities (which had not been released before indeed), even if I would not call them a major find. It's music which is still very much rooted in 19th century and follows its idols pretty closely (without reaching them), even in the late A Minor symphony which strongly echoes Tchaikovsky's Symphonies Nos. 4&6, while the scherzo partly recalls Mussorgsky's Ballet of the Unhatched Chicks in Ravel's orchestration (look at the way Lyudkevych passes over to the trio).

Sadly, however, you will encounter the same attitude in Germany. It is possible to get recordings from the radio archives of the former German Democratic Republic. However, a few years ago I also tried to get some recordings from other (Western German) radio stations, and the result was absolutely zero. I remember somebody phoned me to ask for which purpose I wanted the recordings, and when I replied that I wanted them just to listen to the music by myself the reply was that this was not possible.

Whether the relationship of hidden treasures to the size of the population is really that strong is something I am not too sure about. Each of the Baltic states is really small in terms of population, but what a wealth of great composers there is! Or take Slovenia with just 2 million inhabitants but numerous great composers.

Many thanks for this link, Robert! Very helpful indeed. So it seems that it's the sinfonietta indeed which is meant when talking about three symphonies. The CD in question can be found here:
https://www.discogs.com/de/Stanislav-Lyudkevych-Symphonic-Works/release/14661022
In addition, the Caucasus Symphony-Cantata has been released on a Melodiya LP as you probably know anyway.

What you say about Ukrainian music, Christopher, is true, though it applies to a large number of countries...

Thank you very much for pointing out this recording indeed! My impression is that Lyudkevych's work list often causes confusion (at least when it comes to the lesser-known, not commercially recorded works). For instance, his F Sharp Minor Piano Concerto from 1957 is sometimes labeled No. 2, sometimes No. 3.

With respect to the symphonies, things are not clear either. If somebody counts three Lyudkevych symphonies then the first one could also be his "Caucasus" cantata, which is labeled Symphony-Cantata. The A Minor symphony you found seems to be listed nowhere else. One guess could be that it is the same work the Russian Wikipedia lists as "Suite in A Major" (the work does end in A Major) from 1962. Anyway we can only speculate...

I am remotely interested in the cello CD, as I play the cello myself and the name Piatti is familiar to me. So, getting a chance of listening to his cello concertos will be nice even if I do not expect particularly much.

In general, however, I can only agree with Greg, it's a sad development, thinking of all the British releases from the past one or two decades, and also keeping in mind that still just a few years ago, they did release Steinberg's Turksib, just to pick out one example I was especially delighted to get.

There is a broadcast recording with the Estonian NSO under Kaljuste circulating, however no commercial recording yet.