The background material describes traveling through The Maw as a dangerous event, one that earns respect from seasoned Void-Farers. But the rules have provided no way to show this as anything other than a routine Warp Journey, though perhaps one with a high penalty to the Navigator's skill roll.
I felt that this needed to change, and so came up with the following system which I have been using in my campaign.
Running the Maw is an Exploration challenge based on the Navigation: Warp skill.
When a ship arrives in the vicinity of the Maw, then the GM rolls 2D5 to determine the current conditions along the Koronus Passage. The number generated is how many degrees of success the ship's Navigator needs to get on the Navigation: Warp roll. As with all Exploration challenges, other PCs may support this roll with suitable skills. To date I have allowed Psyniscience, Common Lore: Koronus Expanse and Forbidden Lore: Warp for this purpose.
Conditions in the Koronus Passage are far from stable. Every two weeks, the 2D5 roll is re-made. This means that if there is a high difficulty for the passage when the PCs turn up, they may wait in the hope of a better result. They probably won't be alone, when the difficulty is high then Port Wander and Footfall will be full of ships waiting for the turbulence to clear, and all running for the Maw when an opening appears.
Warp turbulence can severely damage a ship, even destroy it, and this is why most ships will wait out the worst conditions rather than risk the passage. If a Navigator fails to generate the required number of successes, the ship takes 1D5 damage ignoring Armour and Void Shields for each degree short.
If a ship finds itself in unexpected difficulty while running the Maw, then there are islands of relative safety in the form of the Station of the Passage. If the ship is about to take damage, then roll 1D10:-
1: The Temple
2: The Witch-Cursed World
3: The Battleground
4: The Hermitage
5-10: Undefined
This is the closest Station of the Passage to the ship. The "Undefined" ones could just be empty areas of space, but the GM is encouraged to invent others. Yes, I'm aware there are supposed to be twelve of them, but a lot of players won't have a D12. If the GM has a specific plot in mind, of course, then a specific station can be chosen rather than relying on a dice roll.
To reach the Station of the Passage, make a Navigation: Warp roll with a -5 penalty for each 1D5 damage the ship was going to take from Warp Turbulence as described above. Success means the ship takes no damage. Failure inflicts 1D5 damage per full degree, up to the amount the ship was going to take anyway.
The ship is now in realspace in one of the Stations of the Passage. Resuming the journey means making the same Exploration challenge as before, at the same difficulty. If the diffculty was high and the crew have changed their mind about taking the risk, then they can wait at the Station of the Passage and hope conditions improve.