Game works fine, but everytime I go to ship mode, I get a weird graphical glitch that results in the masts and sails stretching into pure-white triangles (Occasionally replaced with different textures) this glitch can fill half the screen, is there a way to fix this?

This game runs on DX8 native with a DX9 wrapper. There are some anomalies in the way they implemented this on some systems especially if you are using an Intel chipset on your machine.

There is a mod on moddb called ENB Graphics http://www.moddb.com/downloads/mirror/20138/113/f50061eabd07d419238051fc9ca6221d/?referer=http%3A%2F%2Fwww.moddb.com%2Fsearch%3Fq%3DENB%2Bgraphics%2BPirates%26sa.x%3D0%26sa.y%3D0

This has helped improve graphics in the vanilla version and several modded versions of the game. It might work for you. I think there is another fix somewhere as well but I can't remember off the top of my head but there is a discussion on how to fix it here: http://www.piratesahoy.net/threads/intel-graphics-fix.19297/

MK