I've been working with previous versions of the 100.0 runtime based family (including the betas leading up to the latest release) and was having trouble opening a scene layer package. I just upgraded to 100.1 and attempted to open my test SLPK and was still having similar problems. I'm wondering if this version (100.1) supports opening SLPKs and if not when that is expected. As info, the scene layer package contains a LiDAR point cloud.
My code is pretty simple...
var layer = new ArcGISSceneLayer();
layer.Source = new Uri(@"file://C:/Public/LiDARDemonstration.slpk");