The Cursed have never been good at running treasure. At all. Ever.
They do have a few options, but outside of these ones you're really going to have to get creative (and expensive) if you want to get gold.
Top 5 Cursed Gold Runners:
I really need this ship lol. Put an explorer on her and you're moving S+L with room for 3 coins. With a price of only 13 points that's about as good as you're going to get with the Cursed. In addition her abilities and fantastic cannon ranks can really help her fight back and/or escape an attack.
2. Sea Monkey
The Sea Monkey is another Cursed ship with S+L speed and four cargo spaces. The same rules apply here; now you've got one less point to spend on other stuff but you get the reverse captain ability.
3. Sea Duck
With or without an explorer this is one of the most effective Cursed gold runners that's cheap and not abysmally slow. Ideally you'll be able to shoot at danger before it gets to you with her ability, but we all know that the best laid plans get ruined, especially in Pirates.
4. Sea Rat
The Sea Rat is always underrated. It's probably because she is a two masted junk, one of the hardest ships to build. She's from the most common set (OE), so some players no doubt have many Sea Rats. In addition, Sea Rat is not an especially flattering name for a ship. However, this ship is a nice treasure runner once you add a helmsman and explorer. L+S, room for 3 coins, 13 points. The added bonus of being able to steal treasure from an enemy HI makes her an ideal gold runner (for the Cursed).
Ugh. I didn't really want to rank these but the other options are so bad that I had to throw them in at the end of this list. The Guichuan would get the nod for the Treasure Ship keyword and being slightly cheaper, but since you are required to use the Headhunter she comes in at 36 points. The Delusion gives you better speed and more abilities that may or may not (probably not) be useful, while sacrificing cargo space once you add crew. The Guichuan is better at being a gunship and a pure treasure runner while the Delusion is better at finding gold, stealing it, and generally just taking up a lot of useless space.
Honorable mentions (in no particular order): Cyclone
, Maman Brigitte
, Fallen Angel
, Hangman's Joke
, Loa's Justice
, Grim Reaper
, Native Canoes
, Dark Pact
If Return to Savage Shores had actually been produced and released, the Cursed would have gotten a ship
. That ship would have been #1 on this list.