Well, ain't life fun.
There are a number of details here ... so absorb them patiently.
First, Ahmet's immediate issue is the artillerist with the flail (pink) and two others with flails (yellow, red). The fellow with the crossbow (green) looks singed, but he's in the process of reloading. No one is holding the space next to the ladder, so as Ahmet climbs up, we will have to begin with initiative again.
Andrej's fire has burnt out. The ladder did not catch.
The roof of the tower is supported by five three-foot diameter pillars. The blue outer circle represents the darkness/ground that surrounds the outside of the castle - I have not drawn in any walls that would logically be below, or features below the level of the tower's crown at all, for the sake of simplicity. For the present, assume that it is all a long, long way down ... and it is. On the side not looking over the castle proper, where it overlooks the exterior ground, the drop is nearly 300 feet.
The roof is peaked and a good 20' feet at its center above the floor.
Now, about this toy in the centre.
It is sitting on four massive gray blocks; there appears to be some kind of fire floating in its centre, about five feet off the ground, which is incredibly bright to look at and which puts off NO HEAT. It is emitting red clouds of smoke, however (best depiction I could manage, I'm afraid).
The spear at its end doesn't seem quite solid; in fact, its either partly phased, or partly invisible. Take your pick.
The long red image shown is a DOOR, hanging about eight feet off the floor, attached to absolutely nothing. There are two guidewires that extend from the door into the heart of the glowing "fire" ... and you can see the door is open and that there are men trying to haul something towards the door. Whatever it is, it appears to be very, very heavy.
That's probably not everything, but lets try this and see. We'll start with Ahmet rolling initiative.