Information given to the PCs about the ship found in Flashpoint:
The boat you found is about the size of a broken pinnace that has run aground against the sandy shore within the large, yawning sea cave. Those with Knowledge Engineering or Profession Sailing recognise that it's a purely fore-and-aft lateen rigged vessel (the triangular sails point forward and back along the ship rather than across the ship) which is unusual for a pinnace. It has a fore and main-mast.
Of course, ships designed primarily with Fore-And-Aft Rigging tend to be smaller, overall faster, and more maneuverable than Square Rigged ships, though this does come with some caveats such as a lower Maximum Speed. This is because wind coming directly from the Port (Left) or Starboard (Right) of the ship will create a powerful pushing force on the sail which is translated into fast forward motion though its smaller surface area means a lower maximum speed.
A ship rigged with Fore-And-Aft Sails will sail fastest when sailing perpendicular to the wind, a sailing point known as "Beam Reach". It can also handle going at other directions, including even Close-Hauled (with the wind coming almost from the direct front of the ship!).
The other unfortunate fact is that Fore-And-Aft Sails are not adjustable being as that they are tied directly to a static mast and a static deck while Square Sails can be pivoted or reefed. This off-sets some of the superb manouevrability of the smaller Fore-and-Aft-rigged ship and allows some brilliant maneuvers with a much larger (and much more heavily-armed) vessel.
So, that aside, this ship has a small, weak hull. It can't carry large trebuchets or other siege weapons without risk to the hull and cannot carry many canons, either. Your best bet is to use its superior speed and turning rate are used to completely outmaneuver one's opponent, dodge incoming fire, and board the enemy vessel early on in the battle.
It also has very little cargo space. Basically, just enough for food and water to last a few months. It has quite the shallow draught and should be able to sail over some Shoals without risk of hull ruptures which would tear apart others.
6 or fewer men can direct it though it becomes quite unwieldy. -4 to all checks to perform any ship-based actions such as turning, reefing sails, or similar tasks. 36 men and women and 10 cannons would bring it to its maximum fighting efficiency though it can carry 60 people.
It can carry up to 25 tons of cargo (including Cannon), which makes it largely unsuitable for trading.
Best Sailing Points: Beam Reach or Broad Beam Reach.
Of course, to gain the benefit of any of this, the ship will need to be repaired and hauled out to sea. Taking a look at it does beg the question, though, what is inside it and where is the crew? It appears to be in a relatively good condition, after all.