BTW, this is on Pi2, running hardfloat.
This install logs:
pi@Kossel:~ $ sudo dpkg -i Repetier-Server-0.70.1-Linux.deb
dpkg: warning: downgrading repetier-server from 0.75.0 to 0.70.1
(Reading database ... 40993 files and directories currently installed.)
Preparing to unpack Repetier-Server-0.70.1-Linux.deb ...
Uninstall Repetier-Server
[ ok ] Stopping RepetierServer (via systemctl): RepetierServer.service.
Unpacking repetier-server (0.70.1) over (0.75.0) ...
Setting up repetier-server (0.70.1) ...
Install Repetier-Server
You may see warnings about groups. These can be ignored.
The user repetierserver' is already a member oftty'.
adduser: The group intserial' does not exist.<br/>adduser: The groupugpio' does not exist.
[ ok ] Starting RepetierServer (via systemctl): RepetierServer.service.
Processing triggers for systemd (215-17+deb8u4) ...