Yes, that’s the reset command. After that set the admin password. Add IP addresses to interfaces which will automatically enable CRS to route between connected subnets. Add default route via gateway and you’ll enable all connected subnets to access internet (via Asus router).
If you intend to use VLANs, then configure those before any IP stuff. Have a look at this tutorial. If your CRS is configured according to tutorial, it will switch between ports (including VLANs) wire-speed.
Routing performance? Check official test results. Seems like routing capacity will be around 1Gbps cumulative (duplex, between all interfaces), give or take. Less if this device was acting as firewall as well.