Unfortunately there is no way to do this yet from Lorwolf itself. However suggestions have been made so hopefully features like such get added! There is a tool here http://lw.fintastic.net/?id=22,194,22,194,22,194,22,194,45,63,1,1 that lets you predict the range of the pups but it won't show you visuals of the actual pup.
@Tiggy adding to caethernyy there's also this spreadsheet which does allow previews but you have to download a plugin, it will automatically give you a prompt when you click on the page for it and it's only two clicks!