Error message hider issues

[Peerly]

So none of the red, center screen error messages appear. Not even the ones that are toggled on. If I disable the entire error hidder module then they all come back...but if I try to hide even one (say the 'not in range' one) then they all go away again. Is anyone else having this issue? I'm almost positive I don't have any other addons that affect these particular messages.

Edit:Actually, the one that's most troubling is 'no line of sight' or whatever, since I heal it is difficult to see when someone is out of sight line if they are showing as in range in Grid.

I've been through my other addons and nothing alters the error messages other than RealUI. I'm not sure how to troubleshoot this.

Second update: I installed ErrorFilter and compared the LUA in both. ErrorFilter works with no problems (other than not having a Blood Charge filter) but it uses different error codes than RealUI. At the moment I've turned off RealUI error hiding but would rather not have another external addon.

Third "update": More question really: Have the error codes changed in Legion? This is, so far, the only explanation I can come up with.