Thanks for your bug report. I have not been able to reproduce this issue. As far as I can tell, there have been no changes to the way local info settings are stored or used.

Can you describe, step by step, how to reproduce your issue? For example, here is what I am trying:

1) Open the Options dialog.
2) Go to the local info section.
3) Type in a valid IP address, such as 127.0.0.1, in the IP address editbox.
4) Press the OK button.

If I then open the Options dialog again, the IP address is still there.

If I exit mIRC and run it again, and repeat the above, the IP address is still there.

If I go to the Options dialog and change the IP address, it is saved, as above.