In Mojoworld pro you can add and combine material layers until the alien cows come home, but Vue 6 Infinite's materials seem more limited at first glance. Granted, I'm hardly a Vue expert. Is there a way to add and combine multiple (at least more than two) material layers in Vue?

In the Material Editor there are multiple ways of adding and combining materials, you can mix materials or add material layers and adjust what percentage of each material should be in the final mix!!!

I don't think there is a limitation for this, you can add as many layers as you want.

Maybe the question was: there a way to mix material layers other than two by two?

Eg: instead of having this:

• Rock
• Grass layer
           - Grass
           - Sand Layer
                    - Sand
                    - Wet Sand

It would be nice to have this:

• Rock (+ distribution rules/map)
• Grass (+ distribution rules/map)
• Sand (+ distribution rules/map)
• Wet Sand (+ distribution rules/map)

I have had cases where it became near impossible to manage due to the fact that you can only mix two materials at a time.

No, you don't need to mix materials with Vue6, you layer materials depending on slope, altitude and orientation, and the presence of the material can also be driven by an alpha function.
So in your case, 1st mat would be rock, the base material, onto this rock you would ad a grass layer, on which you would apply the sand layer, and finally the wet sand layer.
All these loaded oneafter the other, not using mixed materials, but layered materials.

Yup, Bruno021 is dead right.  Use the layered materials in V6.  It is a very complex material system that after a few minutes of understanding is very powerful.

True!
I could use layers.
I followed the tutorial described in the Terrapak manual a bit too closely and kinda thought the mixed material method was the only one useable.

Anyway, I cannot get the results I want with layers either. I am trying to use Geocontrol filtering in Vue. To place the filter map correctly I need object parametric mapping. It works properly if I use mixed materials, it does not if I use layers (materials do not appear where they should).

[edit after further testing] God knows why, it works, but with layers, but using "world parametric" mapping... Vue intricacies will never cease to amaze me :-)

You can also use both mixed and layers....you can add layers to mixed mats but you can't add mixed mats as a layer...

You could, in theory, keep going but I've discovered that after a certain point, if you want to add another mat to the mix, you have to save out the complex mix, load a simple mat and then mix in the complex instead of the other way around....