You shouldn’t “install software in a container”. You really really should build a custom Docker image that contains the software you need, or find a prebuilt image that has it already.
(It sounds like you’re
docker run a base image, then
docker exec into an interactive shell into that, and now are trying to install stuff; but containers are pretty fragile and you will lose the entire container filesystem if you need to change any container settings or run the software on a different system or Docker’s filesystem setup goes awry. This is not a best practice.)
It contains services like SSH, (S)FTP, SMB/CIFS, DAAP media server, RSync, BitTorrent client
That’s a lot of things to be running in one container. In a normal Docker setup those would be a half-dozen separate containers. If you need to run this specific bundled software, I’d run it in a virtual machine. (And indeed it sounds like it’s intended to be installed in an “appliance” with full system administration support; that its download page has ISO image links also suggests it is not built in a way that’s compatible with Docker’s model.)