This is a corrected version of patch 5.8. It had introduced a bug when upgrading walls to blast towers. As this bug was discovered right as I was going on vacation, i rolled back the patch. This is now that patch with that issue resolved.

• Fixed bug where if in the middle of a directional tower upgrade/downgrade and an attack is starts, it would deselect leaving the tower in a 1/2 upgraded state.
  
• Piku Island (The new 7th island) had a few rather interesting traversable routes on the side of some of the steep slopes. These invader walkable areas have been "tightened up". In addition, it was possible to lay a walls with buildings in such a way the "gate blocking" rule didn't trigger, allowing you to block off a path. With these updates it's possible (but unlikely) a save may have used a path that is now not possible, preventing you from placing any walls after the patch. If this is the case, it can be fixed by tearing down walls where its no longer possible to pass, and build new walls.
  
• A few other quite minor fixes.