Rather straightforward and reversible.
Skull’s gator legs are secured to the inside of his robot legs with one small screw. Once it’s unscrewed, the gator leg assembly slides off on a slider. You can flip the gator leg and slide it on backwards and it’ll stay. This compacts the legs, fills in the hollow space, and you can pose the gator legs within to give him more area to stand on. Repeat it on the other side and voila!

Before:

After:

 

Thats pretty cool

 

Just did this on my Krok. Thanks, good idea and tut.

 

holy balls
that's so incrediblöy simple and so effective lol.
now I can have him standing up without falling over all the time

 

Yup, did this about a week after I had him, and the extra stability in the balance is great...

 

I did that same mod almost as soon as I got my Krok! Really improves the look and stability a ton.

 

Does this then require partsforming to convert to beast mode?

 

Yes, it's a fan mod, so if it's partsforming really bothers you then just ignore it. If I'm remembering correctly the Weijiang KO actually has engineering to allow this via transformation?

 

I think so. I've got that version too, but it works be great if the original one did too. Oh well...

 

I've got a part from shapwways that does the same thing.
TR: Crocjoint for reptiles v1.2
and
Titans Return Skull Beast Mode Leg Add-on Parts

 

Nice work!

 

What's the difference between the parts you listed?
edit: I see they are made from different shops...both shops belong to you though?

 

No, I just found them while looking around shapeways.