The way I read the rule the Great Beast only counts as "one bow" when assessing the bow limit of your force. It also only occupies on of the twelve "warrior slots" provided by the use of a hero.
The description says that
A Great beast of Gorgoroth consists of the Great Beast itself (which is a monstrous mount) an Orc Warrior rider with armor and spear (who controls his mount) and 9 Orc Warrior passengers with armor and orc bows (who ride on the battle platform).
This tells us that when you spend the 125 points, you get an Orc warrior that rides a monstrous mount (the beast). This is one model. Additionally you are paying for 9 orc warriors with armor and orc bows. These are 9 separate models, which use their own profile.
The orcs here are not a single model with a combined profile. It seems that GW's intent is to make sure that people used 9 orc archers and only 9 orc archers, not trackers or uruks, etc. It seems easier to just have the crew come with the Beast. If they were all to be treated as a single model, the description would say so.
If we look at the Warg marauder profile, something similar to the beast in that it is one beast ridden by several orcs, it reads:
A Warg Marauder is represented by a single model With a combined profile here- the component parts cannot be attacked or wounded separately.
The Orcs in the battle-platform of the Great Beast model can be targeted and wounded separately. Each crewman (crew-orc?) has its own profile, not a combined shoot value like the Warg Marauder. Including the Orc warriors in the price of the Great Beast streamlined the process of selecting crew and helped (it seems) to eliminate any movement issues within the battle-platform. It seems to me that we are to presume that we can assume every archer has 360 Degree line-of-sight and can be targeted from anywhere )in addition to the in-the-way roll). There is only one tier in the platform. It's essentially a box in which the orcs can freely move.
It is my opinion that because of the description in the Great Beast profile (separate profiles for Beast and orcs), ability to target the Orcs individually, and the comparison to the other new multi-rider model (the Warg Marauder) each Orc in the battle-platform must be counted individually when determining the number of models in the force (for breaking).
The total model count should be 10 (1 for the Driver and 9 for the archers).
That is to say, however, that the Great Beast only counts as one model when determining how many bows a force can take.
For example, if you have 2 Orc captains, 23 orc warriors, and a great beast, then you have 24 warriors and can include 8 bows (1 Great beast and 7 Orcs). When determining break point, however, you have 35 models.
That's the way I read the rule...
I could be wrong though haha
