Problem targeting XLabs in UWP, Droid and iOS

Hi,

I have a PCL profile 44 targeting UWP, Droid and iOS projects.
I tried adding XLabs, but when I try to add a reference to the UWP project, I get the following errors:

1. Type universe cannot resolve assembly: Xamarin.Forms.Platform.WP8, Version=1.5.0.0, Culture=neutral, PublicKeyToken=null.
2. Cannot resolve Assembly or Windows Metadata file 'Xamarin.Forms.Platform.WP8.dll'

Any ideas?