Awesome news. It's working without problems now. Both Ubuntu Server 32bit (i386) and Synology Diskstation 213J+ (Arm) were able to start JDownloader and download files via MyJDownloader.

The source of my project is already available: **External links are only visible to Support Staff****External links are only visible to Support Staff** (the dist directory contains the compiled binaries).
I also uploaded a proof video here: Click

Pro Users already should be able to get JDownloader running. I'll create a HowTo for non-pro users as soon I've got time.