Incorrect Material Assignement to groups

[fedexdga]

Hello,
I have a very strange problem with some object getting assigned random material after reopening a file, and I am not sure where does it come from.
The file it is fairly big, but not out of the ordinary and it didnt give problems until a week ago.
It happens mostly with grouped objects and blocks, just some of the grouped objects gets assigned random materials.
I dont know if this has to do with the latest version of rhino Version 6 SR7 (6.7.18210.11281, 07/29/2018 ) or something else.
I also suspect that it could be related to the use of Snapshots, which I just started (never did before)
This file also use quite a lot of visualarq objects, but because the problem happens mostly with groups of non-parametric objects I tend to exclude it
It is quite annoying and time consuming to fix it, because one never knows if the problem will appear or not...

[Peter.Chaushev]

Hello,

Is there anything in common between the objects (or materials) which are involved in this behavior?
Do you remember when it first occurred?
Could you please make a copy of your project, clear all snapshots data and see if the problem is still reproducible?
We can take a look if you are willing to share the project (either send me a PM or email at support@chaosgroup.com)

Kind regards,
Peter