One of the biggest things to do to make the Baikal more suitable for CAS is reshaping the cocking levers so it stays open far enough to shuck the empties and toss a couple fresh ones in. The firing pins on most, or all, of these come to full cock before the action is fully open. As the action is opened all the way, the firing pin springs are "overcocked" and spring pressure tends to push the opened action slightly closed again until it reaches equilibrium with the cocked firing pins.
The white line indicates approximately where metal needs to be removed to accomplish this. Go slow and function check often as you go. There is a CAS shooter by the name of Papa Dave who sells modified cocking levers for the Baikal if you'd rather go that route - they may or may not work; see 2nd post
HERE for more info.
The auto safety can also be easily modified so it doesn't automatically engage when the shotgun is opened, but can still be engaged manually if desired.