I am on my second different aws OTRS appliance (previously JumpBox now TurnkeyHub OTRS) and am still having a heck of a time getting a functional system setup.
Are you choosing the appliance for at specific reason? OTRS is not too hard to get running, at least on a system supporting RPM packages. Amazon's own AMI Linux is built on RedHat/CentOS and has the RPM system. You could be up and running just by downloading the RPM package from otrs.com and installing it. (As far as I remember, it's been a while).