I was trying to make a CR2 zombie bugbear. So I started with a CR2 bugbear, added the zombie template which made it a CR1, ok good so far. Now I added an additional +1 HD to the zombie bugbear and the CR jumped up to CR3. The Bestiery show zombies with final HD between 5-6 have a CR of 2. I think that is a problem unless their is operator error involved somehow?