Hey, I've been out of town for a while sorry it took so long to get back to you.
I hadn't been setting the "Enable all other monster properties" to true, so I tested it out and now no monsters are spawning at all, even if I try and spawn them through a spawn egg. and in my control panel it is saying that the mod is enabled. What version of the mod are you using? Cause if it works for you and your using it with the most current version of tekkit then there shouldn't be a problem on my end cause I've been trying it on fresh tekkit servers too. Thanks!