I didn't see your post until just now. I just tried it again, but no success.
$ ls -lt total 11824 -rwxr-xr-x 1 gino gino 12098760 Mar 20 23:41 amber-0.7.1-x86_64.AppImage* py[3.7.2] gino@gino-carbon:~/Downloads $ cksum amber-0.7.1-x86_64.AppImage 1839668745 12098760 amber-0.7.1-x86_64.AppImage py[3.7.2] gino@gino-carbon:~/Downloads $ ./amber-0.7.1-x86_64.AppImage Segmentation fault (core dumped) Segmentation fault (core dumped) Segmentation fault (core dumped) Segmentation fault (core dumped) /tmp/.mount_amber-1hbGwe/AppRun: 11: exec: : Permission denied py[3.7.2] gino@gino-carbon:~/Downloads $ uname -a Linux gino-carbon 4.15.0-91-generic #92-Ubuntu SMP Fri Feb 28 11:09:48 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux