Apologies for this post--I'm sure this is a very common problem and has been asked many times, although I couldn't find one that helped.
I am running the latest versions of VE Pro 5 on both Macs: a 2010 iMac (master) and 2014 15" MacBook Pro retina (slave). They are connected via ethernet (for the MacBook, through thunderbolt to ethernet adapter). Both Macs are on Yosemite. When I create a new track in Logic Pro X and create a new instance of VEP, I only get the option to connect to local host and my slave doesn't show up as an option. I've tried manually inputing the ip address of the slave but it still won't work.