My Animated Door ‘breaks’ – is it an NTSC or PAL thing ?

I have a simple animation of a door lock going up and then down, the door closing and then a door lock coming down and going up and the door opening again.

And this happens over 375 frames and it of course loops forever.

I know 100% that this animation is working correctly – as I have done it many, many, many times for this same product over and over in SketchFab, no problem.

However, there is an issue with Verge3D and cannot progress with this project until I solve this issue because I have many doors like this and everytime we have this problem in Verge3D. I have discussed this before with Verge3D and they cannot see the problem, yet that does not make it go away and so I am trying again to get this resolved.

I am on 3DS Max 2020.1. The latest Verge3D (not Beta).

My animation is 375 frames long.

Start of animation the door is stationary and open.

The first thing which happens is that the door lock goes UP.

The Door then swings shut.

The Door Lock then goes DOWN.

What is SUPPOSED to happen is whilst the door is SHUT, the Door Lock is (and has to) goes UP (so that the door can open again).

The Door then swings fully open.

And the Door Lock Goes Down.

And then this is REPEATED OVER AND OVER AND OVER.

This is how it works in the animation, in SketchFab…….but NOT in Verge3D.

So something is wrong in Verge3D.

My animation is in NTSC 30 frames per second.

Please Watch what happens – it’s like the ‘loop’ gets out of sync and the Door Lock is DOWN whilst the Door Swings open and the Door Swings shut whilst the Door Lock is Down also (of course, physically IMPOSSIBLE and not what is shown in 3DS Max as what happens).

Here is a YouTube Link to show you how it behaves correctly in 3DS Max (showing you over and over how it works correctly) and then in the Sneak Peak (showing you how the Door Lock fouls the Door Frame by being DOWN whilst shutting and opening).

Please can someone from Verge3D assist to find the issue and FIX this ?

Thank you.