You need to move logs manually. If you can't move it from one side then you'll be able to move it from the other. It's not really critical to move those but they will let you take more direct paths if you need to.
To unlock the Fencer class you have to talk to the guy in the green hood in the Juki Mining City bar (top-left corner). IIRC you have to talk to the bartender first and complete his quest.
For sneaking past the radio waves you'll need to unlock the Seeker class. According to the official walkthrough, you need to do the following:
- Talk to the NPC in Metus City
- Talk to the old lady in the graveyard to the south of Metus City
- Read the journal in the laboratory
- Find Witch in her house
And then go back to Arle's house, where the event that unlocks the class should trigger (or you have to talk to Satan I don't remember).
That I am yes.