Mike Taylor always does his very best to help folks and is very, very close to being "right on the money". I'll do my best to detail the disassembly/assembly steps in CM84 terms. I'll assume you have the owner's manual that came with the pistol. If not it's downloadable in .pdf format from the Morini website.
Breach Block Removal:
1) Remove electronics and grip
2) Remove complete trigger assembly by removing screw 084099 accessible throught he hole in trigger guard and by drifting out the rear-most small-diameter pin 084056. Now that you have the trigger assembly in your hand, use a soft-bristled brush to remove all the priming compound and other gritty stuff that ends up sitting on the top of the trigger assembly
3) Fully cycle the action to ensure mainspring is cocked.
4) Partially raise the cocking lever 084012 to ensure the breach block is not fully locked in the closed position.
5) Drive out the pin 084015 holding the breach block in position. Note that in the half dozen or so pistols I've taken apart they all seem to like to have the pin drifted out from left to right.
6) Drive pin 084015 holding the cocking lever out from left to right, but only about 1/2 - 1cm as it only needs to clear the thickness of the cocking lever.
7) Breach block and cocking lever should now be ready to be removed through the top of the receiver.
Breach Block Disassembly:
1) Place breach block with its face down against a block of hardwood and depress the sear lever, allowing the firing pin to move fully forward to strike the hardwood (better than a dry-fire which is about the only way you can break one of these firing pins, according to Francesco).
2) Close to the rear of the block you'll find a through-hole which passes through the mainspring retainer plug 084030. Take the smallest hex key that came with the pistol (the one for adjusting the trigger weight) and insert its longest arm completely through the through-hole in the block. This hex key will now retain the retainer plug, mainspring and firing pin as you proceed with disassembly.
3) Remove two Torx screws from tension block 084021 and remove tension block, being VERY CAREFUL not to lose the plunger 084019 and plunger spring 084020.
4) Use your thumb to apply heavy pressure to the mainspring retainer plug, relieving pressure on the hex key holding it in place. Remove the hex key and slowly allow the mainspring to push the retainer plug from its recess in the breach block.
5) Remove mainspring 084029 and firing pin, 084028.
I won't get into specifics here, but I will caution that heavy accumulations of crud, gunk and other undesireable substances will be found in the channel in which the firing pin slides. A cotton swab soaked in solvent followed by a tight-fitting cotton cloth on a wooden dowel is what i use to get all this nonsense out of the hole. You'll also want to clean the firing pin hole in the breach face.
One other area needing attention is in and around the sear mechanism. The sear itself 084033 and its return spring 084034 will be well encrusted in dirt. A toothbrush and solvent work well to clean this area, but be careful not to snag the spring and yank it from its hole. It's small and hard to find on the floor! (Been there, done that!) Also note that both the sear and the sear trip lever 084032 are pinned into the breach block using pins riding in close-tolerance holes. Unless you need to replace the sear, don't even try to move these pins. They're TIGHT and only drift one way out of the breach block (they drift from right to left, or from the smooth side of the block to the side that is machined to allow the cocking lever to move).
Since you've got the pistol apart you'll also want to pay serious attention to de-gunking the extractor 084009 and its return spring 084010, as well as to cleaning the recess in the breach which accomodates the rim of the cartridge case. Build up of contaminants in this recess can lead to misfires.
Re-assembly is just the opposite of disassembly. Keep in mind that you won't be able to get it all put together unless you cock the mainspring first. I use a hardwood dowel to push on the firing pin; this methodology avoids leaving unsightly scratches on the metal.
If you need more details than this explanation offers, don't hesitate to post back here and I'll do my best to help out.