1) scan your waxup, making sure to capture soft tissue landmarks, like incisive papilla. Those soft tissue landmarks are going to be used to align the scans.
2) Start your job and import prep scans and antagonist scan. Enter expert mode and import a PreOp Scan, and select waxup.STL as the scan. When you design your full contour restorations, simply click on the bright aqua PreOP scan for each tooth, and your waxup design will be imported as the full contour design. No need to use a library.