Basic Collision/Physics issues

I am trying to mock up a simple demo in UE4 but I am running into two (seemingly unrelated) basic collision issues.

  1. I have a single large “cube” as a floor, and a smaller cube as a “player”. When I add physics to the player and move it with AddActorWorldOffset it “works” if sweep is off. If I turn sweep on, then once the player makes contact with the floor, I can no longer move it. If the player is a sphere rather than a cube, I can move them with no problem.

  2. I have another scenario. A grid of cubes (8x9) that form the same floor (instead of a single large cube). Using the sphere as a player, it will “hitch” whenever it crosses over from one cube to the next (even though they are touching and level with each other) and eventually the player will just get “stuck” on one of the edges.

I am unfamiliar with how UE4 deals with collisions, is there something I am missing that could solve these issues?