Does the volume and weight of a CBM magically disappear after I install it?
Yeah. Lorewise you’re putting it into yourself, so the Volume has to disappear.
That sounds painful.
Would my character take extra damage from emp grenades?
Can the bionics explode?
No and no. EMP grenades only drain bionic power for now, but actual damage along with enemies dealing it would be interesting.
You have to be sedated to install CBMs, so I don’t think pain is a concern.