What would cause CAT to crash max on a complex model when clicking on Extra Parts button?
It was suggested to hide the mesh first so I am but that is not helping. It would be great to take advantage of the RG3 rig feature.

Ok here is a heads up be sure to un group all objects in your model if you dont it will either crash out max or they will not show up in save RG3 rig.
So in short and weeks of waisted time I got RG3 to save finally. Now lets see if it will be worth the man hours for this. Stuff like this is what makes CAT Suck.

Ok I am going to give you a play by play of this RG3 rig feature and the bull I am going through.
Now I was able to save the rig. BUT dont jump up and down to soon.  Now when i open it I see my hair cap is not on the head anymore and is off in the head by about 3 feet. Hmm ok let me fix that I add a new skin to hair cap to attach to head. Great now I am going to save out the RG3 rig again. NO GO CRASH!!!! Back to sqaure one. Now why would CAT now crash Max?
Fun Fun Be back to you later once i get this figured out.
Mean while six hour into this CAT issue. Are you Starting to see why I think CAT SUCKS and this is just one issue I got a about six other issues just like this that drive me nuts.
Autodesk fix this piece of junk or trash it.

Ok and we are back with successes!!!! This is so stupid that it is almost hard to explain but I will do my best.
Ok so you have saved for your first time add parts rg3 rig and you give it a name lets call the rig CAT SUCKS rig. Ok Now when you open the cat sucks rig and you see something is not right like missing parts of your model or hair that is 3 feet off the head of your model and you want to make some changes to your RG3 rig so you can do things like ah the stupid Ungroup all the grouped object on model because CAT cant see groups and it will crash max if you hit add parts button.  AHHH! weeks to figure that one out folks. 
Ok so now you have made your changes an you are ready to do the add parts again.
Now here is the big trick you need to do to prevent CAT from crashing the crap out of Max with a already save rig when hitting the add parts button.
re select the CAT sucks rig that you named in the list of preset rigs or CAT will crash Max. OH good GOD!!!! Mine was on Ape rig in the pre sets all this time. For the love of God help me.

In short
1. ungroup all group object in model
2. if you need to make a change to rigs be sure to select the name of rig in the preset rig list before hitting add parts again to update a rig.

And Your are welcome.

OH my God I just tried the cat motion editor with this new GREAT RG3 rig and it crashes Max.  With X ref I could at least use the cat motion editor as long as i hide the mesh of the model. What a joke.
Take my advise dont waist your time with this RG3 stuff it is a waist of time just like cat is.

Far Star, I’m sorry to see that you are having so many issues with RG3. And I’m also sorry but it becomes being a little bit funny, too.;-) As you said the CAT SUCKS rig, I had to laugh.

In fact, yes there are some critical issues with RG3. I can assure you the Autodesk team is working hard to fix that. But there are so many things in the list, it just takes time. I think we just have to wait for the next release and RG3 will hopefully be rock-solid. In the meantime, workarounds should do the job.

It might help if you can send me your scene file. I will take a look at it and forward it to the developers if needed.

My CAT demoreel:
http://www.youtube.com/watch?v=Gfq-4VoeAPU

Grack
You have been great for CAT I must say. And I for one thank you so much for all of the learning tuts you have given me with out them I would of been stuck on many many issues back in the day of no docs to study.
I am glad you are seeing the humor in my post I was hoping it would be taken that way. Call it the writings of a mad man at 2AM. I do see the power of RG3 and that is why I have hung in there with this. It can be huge saver on production for sure. 
I will contact you off forum on our production needs with CAT.
Thanks

Ok I now have got RG3 rig working with motion mixer. I forgot that you need to do that monkey busness of hiding the mesh and also go to top view to get Motion editor to open up and not lock up Max.

What do you mean with motion mixer?

My CAT demoreel:
http://www.youtube.com/watch?v=Gfq-4VoeAPU

I ment to say motion editor that I need to do all that monkey business to get it to open. There was another thread on this forum about others having the same issue.

I’m having trouble now with Max crashing when adding rigging or extra parts. As soon as I click the button, a corrupted window appears, Max freezes for a few minutes, then dissapears without saving a recovery. It just gives the error report thing.
It is not a complex rig, just started with base human, pulled it into shape and wanted to add a belly bone to the rig. The mesh is hidden and not even skinned to the rig yet.

This is what I see when I press the button.

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