yEd package installtion difficulties in NixOS

Dear Nix community,

i would like to ask a question about my issue.
GitHub issue

I would like to install the package mentioned in the topic.
However adding the yed in configuration.nix I’m unable to rebuilt my system.
I’m receiving this kind of error:

trying https://www.yworks.com/resources/yed/demo/yEd-3.20.zip
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   219  100   219    0     0   1037      0 --:--:-- --:--:-- --:--:--  1037
100 29261  100 29261    0     0  88939      0 --:--:-- --:--:-- --:--:-- 88939
unpacking source archive /build/yEd-3.20.zip
[/build/yEd-3.20.zip]
  End-of-central-directory signature not found.  Either this file is not
  a zipfile, or it constitutes one disk of a multi-part archive.  In the
  latter case the central directory and zipfile comment will be found on
  the last disk(s) of this archive.
unzip:  cannot find zipfile directory in one of /build/yEd-3.20.zip or
        /build/yEd-3.20.zip.zip, and cannot find /build/yEd-3.20.zip.ZIP, period.
do not know how to unpack source archive /build/yEd-3.20.zip
builder for '/nix/store/279z8s0p2pcpnq45sg1rrzf2d6s2pxrh-source.drv' failed with exit code 1
cannot build derivation '/nix/store/sy2d5mzvj5lf46kz01bx48c1kmabvis2-yEd-3.20.drv': 1 dependencies couldn't be built

I just cloned whole Nixpkgs directory from the GitHub and I was able to build mentioned package by invoking this command:
nix-build -E ‘with import {}; callPackage ./default.nix {}’

Could you please tell me what I’m doing wrong?

The problem was identified.

The branch 20.09 has package for the previous version 3.20
The current version is 3.20.01 and the package is available in the main branch.