It's definitely not my machines/connection; tried on two different networks, two different computers (10.10 and 10.11), with Chrome/Safari/FF on each. Download starts at 32kbps and then eventually times out every single time.
Does anyone have the .pkg installer for RM 1.5.40 they could send me? That's probably against Kemper TOS but the official download itself isn't working so I'm not too concerned about that.