[choo-chee]

well when motion blur is ON only the original MXS referenced object is rendered.
Duplicated (special) objects are not.

[Mihnea Balta]

There is a bug in the engine related to instanced MXS references when motion blur is on. The only workaround is to disable "Maya Instances to Maxwell Instances", but in that case the references will be copies, and will use more memory.

[choo-chee]

can you tell me is there a fix coming for that bug...?
duplicating all the trees and other stuff I have will probably make my computer explode ...

[Mihnea Balta]

I don't know at this moment, but I will ask.

[AlexP]

Is it related with camera motion blur or with object motion blur?

[choo-chee]

I have a car moving from left to right.
When the car is rendered without motion blur all the other refs. are good
When motion blur enabled than most of the refs. are gone and become small emitters ...

[Mihnea Balta]

It doesn't matter if the camera or object are moving. The issue appears when motion is exported for instances of MXS references, even if the motion is very small.

The problem could be avoided by turning off motion export for those instances, but the plug-in doesn't have this option at the moment. We'll try to add it for the next build, but I don't have an ETA for it yet.