I admittedly did a pretty poor job on my character controller. The non-sliding being the biggest problem so apologies for that.
As for the 2nd issue, if I'm understanding it correctly, the ability to interact is tied directly to what the player can see in the light. So if an interaction is too far out of the lights range you wont be able to interact.
I'm glad you enjoyed the atmosphere, it seems a little rain audio goes a long way :)!