Progressive Morph Targets

Does anyone have a solution for using the Progressive Morph feature in 3DS Max with Verge3D? I’ve attached images of relevant puzzles below.

I’m basically trying to create a product customizer using morph targets that are driven by sliders (3D geometry for now). Here’s what the puzzles for the majority of my sliders look like.

However, there are a couple sliders that need to be progressively morphed through multiple targets to give a smoother animation/transition.

I’ve already tried doing it using a keyframe Morph animation with the Map to Range function.

The issue is: if I set the other (regular) morph sliders in my project and then try to use the keyframed morph target slider, all the other morph targets are completely reset and only the keyframed slider affects my mesh. Doing it this way, I’m pretty sure I also wouldn’t be able to have more than one keyframed morph slider, because I won’t be able to blend between those two animations.

Does anyone have a solution I’m not thinking of? I’ve looked everywhere on this forum but couldn’t quite find anything on this.

Also, I’m using 4.0 so the number of morph targets hasn’t been an issue. I have 10-20 other sliders that are just blending a single morph target between 0 and 1 and they all work great when used together.

Thanks!