Sorry to revive an old thread, but has this ever been solved? I have the same situation. The whole solution to me for IT Automation, was that LAN watch would be able to to just this,
The problem is in the ARP request following the ping when doing LanWatch. It can't be routed. The problem will be there until Kaseya implements this in Network Discovery or re-design LanWatch. I agree. There should be a possibility to scan multiple IP ranges fom one central point.
Can I just query (just curious) what are you using Lanwatch for? as in why do you want it to scan the other subnets.
Basically I would really like to deploy the agent o one PC, do a company wide LAN watch scan, and deploy the agent from that one PC. I really felt that Kaseya had a strong selling point on just this one function.