I have updated the releases for Last Action and Audit Log Enhancements, Ticket Attachment Tabs, Required Watcher to both the 5.2.x and 5.3.x API's. You can read more about them here.
Last Action and Audit Log Enhancements - http://cerb5blog.com/project/auditlog
Ticket Attachment Tabs - http://cerb5blog.com/project/attachmentstab
Required Watchers - http://cerb5blog.com/project/requiredwatcher