Undo & redo the settings for allowing iTunes to import songs. ie: 1. iTunes preferences -> Advanced -> Copy Files to iTunes media folder.

2. LW's menu bar, Tools -> Options -> Files, scroll down to iTunes & click option for it & disable this option, click apply or OK. Then go back & enable it again. Click OK.

If you wish to have the LW playlist also show in iTunes then go to iTunes preferences -> Sharing, click option for Look for Shared Libraries. (Equivalent option also needs to be enabled in LW's iTunes option which is listed below the option in 2 above.)