I use a trial version mikrotik-6.33rc36.iso for PC(x86) with Hyper-V on WS 2012 R2.
If I set in the properties of the virtual machine more than 1 virtual CPU, then stop working network interfaces (ping is not working). Himself pings. This is as it should be?

from ISO you are installing normal RouterOS that no-to-limited support for anything virtual. Wait for CHR licensing disclosure.

Same problem here! CHR on Hyper-V, single CPU core has poor performance and when I try to add another CPU core, it doesn't works.

Jarda