When XamCarrouselListBox is hosted in xamTile strange behavior occurs while resizing. In some moment XamCarrouselListBox’s items’ path is not properly resized. Found so far is that  tile’s constrains  affect the moment (size) when problem occurs. In attached test solution the problem can be reproduced when you maximize the window.
We are using version 10.3.20103.2018.  We have not experienced such issue with version 10.2.20102.1014.
Find attached demo solution (you have to set path to your sample pictures folder on your Windows (e.g. “C:\Users\Public\Pictures\Sample Pictures”) in Window1.xaml.cs:27

Steps to reproduce:
1. Maximize window
2. Maximize tile – path takes all XamCarrouselListBox
3. Make tile normal size
4. Path in XamCarrouselListBox takes only part of the tile