Sounds like you've pushed the memory and system swap file beyond it's capacity.

You can load a large amount of procedural textures (applied to primatives),and even though Metaballs take a considerably longer time to render because of their design to mix the materials applied to them, the memory load isn't maxed out.

Once you import an object that has large/Hi res textures(with bump/texture mapping), Bryce adds all of those into the file size, and configures the mapping. This requires lots of memory.
Not sure if upgrading would solve this issue. Doubtful in my opinion. I can Crash any version of Bryce by overloading the memory buffer.

Have you tried creating a second file with the Vicky and then merging the two files?

There are other methods to workaround this scenario.

 - Loading the V-OBJ with no materials, and then adding them manually, saving the file as you go. Inevitably your Bryce may crash once it has exhausted the memory and swap capacity of your system.

 - Rendering two seperate images with the same enviromental settings, creating alpha mask renders and combining the seperate files in a 2D enviroment, though you have to be comfortable with creating certain attributes in a 2D form such as shadows and reflections.

 -  Increase the memory in your system, and/or create a larger system swap enviroment with a larger Hard Drive.

I'm sure others have run into to this situation and can offer some assistance.

Good Luck, Let us know how you make out.
ICM

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Ockham's razor- It's that simple