This is a derived question from this one​.

Maha Nadarasa received his answer there, but I have no clue what is going on.

In some assemblies (not all) when I try to insert a new part, the main body of assembly disappears.

A short movie and a sample assembly is attached.

Here's a bit about my situation:

OS : Windows 10 Enterprise x64 with latest updates.

Graphic Card : NVIDIA Quadro K600. Drives are downloaded and installed from here​

SW : Solidworks 2018 SP0.1

Once again, not all of my assemblies show the same result. Up to now I have only two assemblies that can reproduce this.