Start Titanium Backup
-On the top right hand corner there should be a little white box (at least for Nexus 7) CLICK IT.
-Should bring up a menu Batch actions -ALL
- Click on Run, next to where it says Restore missing apps with data
-Then choose the apps you want to restore by making sure there is a check mark next to the name
-After you check all the apps you want back just click the green check mark at the right hand corner and let it do its thing
Hope that helps
PS. Make sure you have backups of your apps before installing new rom by clicking Backup new user apps & newer versions. thru the same menu.