Hi,
Just to clarify - system password (which is affected by the setting Password Security in System module, just as the checkbox "Password never expires" is totally separate thing as StandardID and its password.
Basically each user in the system has 2 password - StandardID password and another local - system level - password.
When you create new user and system asks you to change the password, I am quite certain we are talking about System level password change, not StandardID password change.
good question, though, is why you are not getting requests to periodically update StandardID password - you should.
Can you provide at least one StandardID (e-mail address) so we could investigate why the user has not received request to change its password?
Regarding special characters used in the password - there shouldn't be any. If there are, please reach out to me with a bug report and I will get it fixed.
Martins.