Detail Normal maps not working correctly

While experimenting with the normal and detail normal slots in the materials I found that the detail normal is quite bugged ... Firstly it always applies to the 1st UV of the mesh, no matter what UV layer you have assigned it in the material editor, so : UV layer : 0 = detail normal applied once on the 1st UV of the mesh and UV layer : 1 = detail normal applied once on the 1st UV and another time on the 2nd UV. Below I'll attach some photos which should make it easier to understand what I'm talking about:

1. How the correct materials look, this is achieved by actually switching the places of the normal and normal detail maps, only the normal UV layer works correctly, while the detail normal UV layer only works correctly if set to 0 :


2. How the materials look with no detail normal ( strength set to 0 but it works as if it's not present ) :


3. How the materials look when the detail normal has UV layer : 1, as said above this applies the texture on the 1st and 2nd UV of the mesh as opposed to just the 2nd, you can see how the normal map repeats itself as the 2nd UV is mostly a scaled up version of 1st one :


4. For some reason, altough not sure if this is caused by the detail map or not, because this happens even if it's not assigned, the strength doesn't work as it should, when set to anything under 1 it looks like it's actually set to 1 and only works if the strength is higher than 1 :