Hello Johannes,
Unfortunately, I don't know if there are older releases of ARC available :( I was using Appcelerator's Titanium Developer to build the releases. It would automatically take the sources and compile the installers, then place them on their own servers for download. The downside of this approach is that every time a new release was published, Titanium would not give me the URL to older releases any more.
I have kept the links to the installer files of older releases and just re-enabled them in our Downloads section. I have no idea if they work anymore, but at least you can try and tell me if that works! Link to the Downloads section for Akeeba Remote Control: https://www.akeebabackup.com/download/official/akeeba-remote-control.html
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!