Using Sli3er for multiple items. Latest version.

I was wondering if there was a way to slice multiple items on the same platform differently? Such as printing one item with 20% infill, another with 50, and another with 90? Or change infill styles between items in the same print job in case you wanted to create sample examples of each?

Also I received notice when clicking slic3er's config button in its tab in Repetier saying there are updated versions available? How do I find the latest version of slic3er that is designed to accompany Repetier?