Bump mapping looking weird

[mantaskava]

Hey guys!

Trying out corona for the first time and I ran into this issue (image attached) with bump mapping.
I imagine I should get this kind of look if it was set to UVW mapping and UV maps were wrong (although mapping is set to cubic).

So what is the problem here?

Thanks.

[Dennis]

Try deleting the Normal Tag and make sure your Poly is planar.  Maybe even rebuild that poly to make sure its clean

[mantaskava]

Yep it looks like it was normal tag's fault.
Thank you Dennis!
Tho I want to ask you couple more questions:
When and why should I use Corona's "Bitmap" shader and Corona's "Output" shader?