ETS integration is mainly for an engineer who has the ETS on their desktop to be able to launch the tools while browsing their Orion server. It's not meant for installing the toolset on the server and allowing multiple people to run it from there.
That being said, someone did work on a way around that - you can find it here, not sure if it works for all tools though. I'd bet not....
Orion-Toolset Integration Trick: Sourcing ping and traceroute from the Orion server
Haven't tried it myself, and looks like he's only done it with a couple things...