Hello there! There is a small issue when tiling a material inside the 3D Viewport of Sampler. When setting the tiling higher, the normal intensity increases aswell. Here you have a picture comparing the same texture area with a different tiling setting. 
This becomes a problem when trying to checkout the material for tiling issues, the material becomes very noisy and not representative of the information of the texture.
Thanks for the help and a great software!