deb2appimage won't build ScummVM AppImage on Xubuntu 22.04

[Auster-1]

I get this log:

Executing prerun...
Downloading dependencies...
Extracting dependencies...
Preparing AppImage AppDir...
Executing postrun...
Using 'appimagetool' to build AppImage for 'scummvm' to '/home/auster/Misc Programas/ScummVM/ScummVM.AppImage'...
appimagetool, continuous build (commit b719a7f), build <local dev build> built on 2022-09-29 13:55:16 UTC
Using architecture x86_64
/home/auster/.cache/deb2appimage/AppDir should be packaged as /home/auster/Misc Programas/ScummVM/ScummVM.AppImage/scummvm-2022-07-22-x86_64.AppImage
Deleting pre-existing .DirIcon
Creating .DirIcon symlink based on information from desktop file
AppStream upstream metadata found in usr/share/metainfo/scummvm.appdata.xml
Trying to validate AppStream information with the appstreamcli tool
In case of issues, please refer to https://github.com/ximion/appstream
scummvm.appdata.xml
  W: scummvm.desktop:4: cid-desktopapp-is-not-rdns scummvm.desktop
  W: scummvm.desktop:12: circular-component-relation

✘ Validation failed: warnings: 2, pedantic: 1
run_external: subprocess exited with status 3Failed to validate AppStream information with appstreamcli
Error Running appimagetool!
appimagetool failed to build scummvm
Exit code 6

This is the JSON code I am using:

{
   "buildinfo":[
      {
         "prerun":[
            "curl -sL https://downloads.scummvm.org/frs/scummvm/2.6.0/scummvm_2.6.0-1_ubuntu22.04_amd64.deb -o ~/.cache/deb2appimage/debs/scummvm.deb"
         ],
         "name":"scummvm",
         "version":"2022-07-22",
         "deps":"liba52-0.7.4,libasound2,libc6,libcurl3-gnutls,libfaad2,libflac8,libfluidsynth3,libfreetype6,libfribidi0,libgcc-s1,libgcc-s1,libgcc-s1,libgif7,libgl1,libglew2.2,libglib2.0-0,libgtk-3-0,libieee1284-3,libjpeg8,libmad0,libmpeg2-4,libogg0,libpng16-16,libsdl2-2.0-0,libsdl2-net-2.0-0,libsndio7.0,libspeechd2,libstdc++6,libtheora0,libvorbis0a,libvorbisfile3,scummvm-data,zlib1g,beneath-a-steel-sky,drascula,flight-of-the-amazon-queen,fluidsynth,lure-of-the-temptress",
         "repoarch":"amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,amd64,all,amd64,all,all,all,amd64,all",
         "distrorepo":"Ubuntu",
         "repoversion":"jammy",
         "binarypath":"/usr/games/scummvm",
         "desktoppath":"/usr/share/applications/scummvm.desktop",
         "iconpath":"/usr/share/icons/hicolor/scalable/apps/scummvm.svg",
         "usewrapper":"true",
         "postrun":[
            null
         ]
      }
   ],
   "apprunconf":[
      {
         "setpath":"true",
         "setlibpath":"true",
         "setpythonpath":"false",
         "setpythonhome":"false",
         "setpythondontwritebytecode":"false",
         "setxdgdatadirs":"false",
         "setperllib":"false",
         "setgsettingsschemadir":"false",
         "setqtpluginpath":"false",
         "exec":"/usr/games/scummvm"
      }
   ],
   "authors":[
      {
         "type":"Author",
         "author":"ScummVM",
         "url":"https://www.scummvm.org/"
      },
      {
         "type":"AppImage Maintainer",
         "author":"Auster"
      }
   ]
}

It sounds like the issue could be with AppStream, but I couldn't find anything about it on AppStream's page. And it also sounds like appimagetool may be related to the issue, but there's also issue #21 which makes it sound the problem could be on either the deb file or the deb2appimage tool itself. Due to all those observations, I'm not really sure what to do.