Problem importing high resolution raster images to ConceptStation

Hello,

I created a new project and added a high resolution terrain.

I then proceed to import .tif (raster images) as shown in this tutorial video: https://www.youtube.com/watch?v=seiXLrM5pPs

Somehow my image comes up with a green transparent color as if terrain wasn't draped correctly (see image below.

Any suggestions how to fix this?