Appstore doesn't work

3G 3.1.3 MC011LL Spirit JB

Since JBing, I had not tried the appstore, until I got an update for a program I bought. When I tried to Update i get the "waiting..." message when a program is about to download, then i get a pop up that says "Unable to Download Application. [Program Name]will be available for download when you log into iTunes store on your computer"

I checked for updates in iTunes, and it downloads the updates, But nothing happens when I sync the iPod with iTunes.

1) is there a way to update my purchased apps through appstore on iPod?
2) How can I get my apps to sync?
3) Am I missing some plug-in for a Jailbroken iPod to be able to do this stuff?

I searched the web and Have tried various things, but they were all suggestions from ~2years ago, nothing recent.

Thanks!

ok I will try that, But before I do, How can I save my stuff? Since I can't sync to iTunes, I don't want to loose all my information/save games or have to hunt for all my programs again. I've heard about this program called Applesync, does that work?