Thanks for your questions. Hope I can help out ...
1. You're right in that my map is misleading (the river is a bit too wide). That said, the multiple swim checks were an intent to convey the danger of swimming the swift current, without simply bumping up the DC to unimaginable levels.
The "crossing safely/unsafely" was done in mind that the PCs will be under attack by the goblins the entire time --- devastating to low level PCs and a serious tactical nightmate if the heroes don't think it through. As in all games, ultimately it should happen "at the speed of plot."
2. The cliff is on the back side (south and east) not the dock side. Sorry for the confusion. On the map you can see where the wall ends on the east --- this is where the cliff begins.
3. Hunters Way is blunder on my part. You are right to play it that no one from Wildsgate normally crosses the river to the north.
Ogre Trap: "He" is swinging on block and tackle. No dropping or crushing. Sorry.