The posts aren't being deleted. You just have to go to the bottom of the page and tell it to display the last 3 months, 6 months, 1 year, or all posts. It is defaulting to display three months.
For example, click on Tips and Tricks, then scroll all the way to the bottom and there's a box entitled "display options".
BTW, don't think I don't appreciate you working on this.
And I hope you don't have cause to regret the custom avatars!
