Liesbeth Levick

The issue seems to be that your skin is coming in along with the hairs in the IN_HAIRS_HEAD LOP.

In SOPs, where you prep for export to Solaris (or anywhere really), instead of object merging "/obj/HEAD_HAIRS/OUT_GROOM", I recommend always going for the unpacked "/obj/HEAD_HAIRS/OUT_ANIMGUIDES" instead. When I use that the problem goes away.

Also, if you do want to subdivide your skin at rendertime, on your Hairgen OBJ node, under the Skin tab, set the Subdivision mode from "Match Skin Object" to "Always On". The matching only works for Mantra. We are looking into options for doing this in Solaris in the future.

P.S. In the other thread I suggested using more guide curves if you wanted better coverage... well, looking at your file now I see that that is definitely not your issue!

This looks great! If this were my groom I'd try the following to push it to the next level:

Does the tip of your hair width reduce to zero? If so try increasing it a touch. Your overall hair thickness might need to be bumped a tiny bit to give it a bit more definition.

The hair direction is also a bit too random, especially on the top part. You might need to increase your guide count to get a really nice spherical shape in the hairs if you're struggling to get good "coverage" otherwise.

Judging by the lack of white in the bottom half of the shape, I think the hairs need to be pointing a bit more to the camera at their roots, and then just the last little bit curves down a bit under gravity. I don't quite get the sense of a round ball of fur with just that single segment, like an orange segment, removed from around the face. Perhaps it is like that and is just being flattened a bit by the lighting/shading. (If so, maybe play with the Medulla radius in the Karma Fur shader?)

Lastly, in grooming, it all comes down to the clumping. Yours is really good, I think it could just do with a touch more strength to really get that definition.

Have you tried changing Houdini interface to use Z-up, to match Blender's. Go to Edit->Preferences->3D Viewports and change the Orientation to Z-up.