There's 2 way to enter value for textures. Angrypig explained it in another thread. You can enter value like 0 , 1 , 2. ..... up to 255 or use a decimal value like 0 , .01 , .02 up to 1.0
So when you enter 1 it actually equal to something like .03 roughness. To have 1oo% roughness you need to enter 1.0 or 255
Nice model you have there. The texture works really well. I got myself into playing with texturing a small medieval village i found in sketchup warehouse to experiment with texture. The hard part is to find good textures photo. So far the best place to find them is using google street view. For medieval stuff, you just need to find medieval village. The resolution is often good enough (if the building is not too far from the camera)
Anyway, i might use your well if you make it available.