Works very well it seems.

Here are a few things I noticed.

There is no way to add flags to objects (like insta-gib or non-grip).

It would be helpful to be able to clone objects.

It would be helpful to be able to mirror objects (across different axis)

There should be a setting to make both players have the same body modifications.

Uke is floating off the ground at default position (tori is standing on the ground, despite having the same z positions)

There is no way to add triggers to body parts.

It would be a very nice feature if you could "trick" the centre into being 0 0 0 rather than 1 -0.1 0.
I'm guessing that if you physically change the position of the centre, all the old mods will break, but if you could just make it so the editor takes the position and adds -1 0.1 0 to the x y z co-ordinates and displays it as 0 0 0 it would make everything much easier.
I hope that makes sense.

-- Can't add flags to body parts

I can't seem to load mods, is that just me? I had to rename the mod to modmaker.tbm to load it.

When clicking on a text box to change a number, it would be better to be able to edit the number rather than have it disappear and you having to type a new number in.

No way to change the size of alt (grip) hands.

The winner on collide setting would probably make more sense as you and uke like the body modding rather than left and right. Or it would to me anyway idk.

No way to edit the engageplayerposition setting (or rotation)

I'll add more stuff as I find/think of it.