When setting the first FK, you will see a sphere marker appear in the APEX autorig component at the point of the skeleton. When setting the first FK
Can this size be changed?

I understand that it can be changed in Apex Configure Controls, but I would like to make it larger or smaller in one go.

As far as I know that cannot be changed without some tinkering. That's the size of the default controller when you initialize your rig.

You could attach the controls to the skeleton before you pack it into APEX format. Will Harley shows how to do that here -> https://www.youtube.com/watch?v=-0KbPtoP5MU&ab_channel=Houdini [www.youtube.com]

somewhat related
https://www.sidefx.com/forum/topic/93248/ [www.sidefx.com]