Just going to make sure, but are you sure you placed all .fhm, .fho, .fhs (if provided) and .fhw (if provided) into Local Disk (C:) \\ FeralHeart \\ exports. If you have then you should be able to see and enter the map through it's portal. Thing is, the custom map portals are so difficult to see in Cape of Distant Worlds because of how transparent and how dark the area is. The first portal will be found directly to your left or right, behind the small hill where the stone arches are.
If you're still having a hard time finding them, I suggest you download and install my portal mod to the game. Custom Portals - Improved (http://www.feral-heart.com/smf/index.php?topic=58069.0)