Do you have a "#" sign, "$" sign or a ":" in your main password? The pound sign absolutely cannot work because it is the terminator for all AP commands. In other words, if your password is:
12345#67890, when you try to tell this to the GTOCP4 or CP5 through the webpage, the command will terminate at the "#" sign. The CP4/5 will take the password to be: 12345.
The ":" and the "$" sign are how commands begin, so although the may work, they are best avoided in passwords. All other letters, numbers and special characters are fine to use.