My IP.Chat installation is still showing bugs that, according to the bug tracker, should have been fixed in 1.4.1.

For example: http://community.invisionpower.com/tracker/issue-36551-private-chat-member-leaves/

Is there an updated version somewhere that includes these bug fixes?

Version 1.4.1 is available in the client center, and is the latest release available. The bug you linked to is marked fixed in 1.4.1.

Be sure that your skin templates are up to date, and that you have cleared your browser cache (to ensure that the javascript file has updated in your browser). Beyond that, submit a ticket if you require support.