When I use Michael 4 and before I try to apply a photo in the face room, I get the message:
"Your selected figure is not a known Face room figure. Applying heads from the Face room may work...."

Why is that? Isn't Michael 4 useable in all the rooms in Poser?

Michael

Daz figures aren't made by Poser's company. The Face Room only supports some of the Poser figures. 

Of course, most people use the Daz figures because Poser figures tend to look really strange and aren't proportioned all that well. I suspect the Face Room isn't used all that often by anyone. 

Grab PhilC's Poser Toolbox, which has a Face putty feature, which is similiar to Poser's face room in python format, but you can use on any figure.

-- Jeff

Poser's Faceroom only supports the figures that actually come with Poser with the one exception being ApolloMax.

Does FacePutty do textures? I say that because that's what the OP appears to be trying to use the faceroom for, not morphs.

Miki 2 and the G2characters (James, Jessi, Olivia, Koji and Kelvin) available at CP are also supported. 

I like the poser 7 characters, except the shoulders are too rounded.  DAZ characters are on the tall spindly side...

 The actual technical reason is that for a figure to be useable in the Face Room, there has to be morph control mapping into the face room system, as well as surface control of all the polypoints. That process is both timely and costly. Poser's owner(s) have set a cost to do it, and DAZ has said they will not pay it. So it isn't some bug in Poser, but DAZ refusing to pay to have their figures set up for use in the faceroom...

Actually, CP does provide G2 faceroom data files for free.  Need to be a registered member, but well-worth it if you want to pursue developing custom face morphs with these models.