MyBB Hacks

I need a help..
how to display the contents of the last thread in the index??

If I don't misunderstand what you mean, if you already have a plugin that displaying latest threads in index and the plugin pull all the rows in threads table out, similar to the latest threads block in portal, probably you can use Thread Tooltip Preview plugin for displaying the preview of the thread contents.

Example how to do it with the latest threads block in portal:
http://mybbhacks.zingaburga.com/showthread.php?tid=565
And the screenshot:
http://mybbhacks.zingaburga.com/showthre...http://mybbhacks.zingaburga.com/showthread.php?tid=565&pid=44