object doesn't support this property or method when calling a function

You don't have to use variables. Your code in cmdClose_Click in the Form_Incidents module says:
Call LogError(Err.Number, Err.descripton, "Incidents - check_values")

If you change that to
Call LogError(Err.Number, Err.Description, "Incidents - check_values")

Then it will work. The reason making variables worked is that Description was spelled correctly.
Otherwise it was correctly complaining that Err doesn't have a property called 'descripton'.

Note that the fact that VB didn't auto-capitalize for you was a hint that you had misspelled the property name.

Thanks Shane. That should have been obvious to me. I think I should take the rest of the day off. :banghead:

Welcome to AWF Shane

I recognised your user name & having just checked your profile, I now realise why.
I hope we will get the benefit of your detailed knowledge of Access on a regular basis.