Normal map seam problem + artefacts in xnormal

I have a problem with a rather ugly seam on my normal map, I am using 3ds max, mudbox and xnormal.

workflow

1 ) made the low poly in 3ds max (editable poly)

2 ) unwrapped it

3 ) exported as .obj from 3ds max

4 ) imported lowpoly .obj into mudbox

5 ) sculpted highpoly based on low poly

6 ) exported highpoly as .obj from mudbox

7 ) baked the normal in xnormal using the low and highpoly .obj's (has some artifacts, no idea how to fix it)

8 ) applied normal map in material in 3ds max

normal map seam (all channels normal)

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/normal%20map%20seam.jpg]

normal map red and green flipped

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/red_green%20flipped.jpg]

wire on normal map

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/wire%2Bnormal.jpg]

checkers

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/checkers.jpg]

the entire mesh is on a single smoothing group

How do I use a cage in xnormal?

Thanks, the cage fixed the artifacts, but damn... xnormal is one cluncky piece of software ...

The seams are still there.

I added an extra edit poly modifier above my unwrap modifier in the stack and I assigned each island a different smoothing group, so no groups touch eachother with the same smoothing group (body = 1, legs = 2 should each island be unique as, in each leg their own unique group instead of all legs in smoothing group 2?), exported it to .obj. and rebaked it, but the issue still exists.

Isn't there an easy way to select the uv islands via the uvw modifier and assign smoothing groups there?

I applied a single smoothing group again after the bake, applied the normal map in a the diffuse slot and even there it is visible

what else can I view it in?

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/Screenshot%202014-04-22%2018.17.10.png]

I 'll try marmoset toolbag

but I am pretty sure the green channel isn't the issue.

Here is it flipped

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/Screenshot%202014-04-22%2018.25.45.png]

yes, it shows that seam in every bake I did so far, even with the channels flipped

@ ayzon: I am not sure what you mean, but the model is a single mesh
@ paranoidMonkey: I had my edge padding at 2 pixels the screenshot is scaled down and it's hardly noticable, I 'll keep in mind to use more padding in the future

@ Minos: I really hope that this is the case, it's been driving me crazy and causing a headache for 2 days allready ...

But does it explain the seam when the normal is applied as a diffuse?

I 'll update once I get it to work in marmoset.

EDIT: baked an object space normal (shows no seams) converted it with handplane to a normal tangent map (shows seams)

Some progress!

seems like its a problem with how the tangent is read

somehow it work in marmoset toolbag set to 3ds max's way of reading the tangent normal but not with the one from xnormal (which was used to bake the map)

Guess I shouldn't worry about the seam, but just to make sure to use the right tangent for each software

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/Screenshot%202014-04-22%2022.24.09.png]

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/Screenshot%202014-04-22%2022.19.58.png]

didn't know that, how? if I can render them at x +, y - and z + they should be correct for the cryengine

edit, found it, in the map to render the 3dots behind the normal map checkbox thingie

hmm, guess there is still something wrong after all ... rendered in xnormal x+ y- z+ , which should be correct for the cryengine, flipping green makes it even worse

[Blocked Image: https://dl.dropboxusercontent.com/u/16324432/horse%20normal%20seam/ingame%20seam%20visible.png]