I'm teaching myself scala and have been using IDEA with the Scala plugin as my IDE. As such, I've been looking at and loading a lot of existing code/sample code, but while most of the code compiles and runs fine, IDEA lists a ton of errors. I've seen other discussions here about this.
One example of a fairly complex Lift based app is from the Lift book at http://github.com/tjweir/pocketchangeapp/tree/master. It would seem to me that looking at projects like these and making sure they all load in IDEA with at worst yellow status would help get things like import handling in line.