Documentation for $ZMLKHASH
It was added for use in our regression testing and is not supported for use in applications.
GT.M does not currently support ARM processors.
This looks like an issue which was fixed in GT.M 6.3-010. http://tinco.pair.com/bhaskar/gtm/doc/articles/GTM_V6.3-010_Release_Notes.html#GTM-9190 Note that 6.1 is over ten years old, so it isn't surprising that it doesn't work well with much more modern operating system releases.
You have the 32-bit GT.M release; you want the 64-bit one, with x8664 instead of i586.
You have the 32-bit GT.M release; you want the 64-bit one, with x8684 instead of i586.
No, the server should be fine. You can get (a somewhat older version of) GT.M from the Ubuntu package manager as fis-gtm, which will take care of all the required runtime dependencies.
You need "devel" packages for these. So libicu-devel, libconfig-devel, and gpgme-devel.