As replied via email, our trial is for the latest version and is meant to see if the latest version is something you can work with. An older version makes no sense in that light. We're not affiliated with Atlas in any way, you don't need LLBLGen Pro to run Atlas' software. You need it to adjust the schema of your Atlas installation, as far as I know. So, no, you can't use a trial of our software to adjust your Atlas installation.