I downloaded again but no change. perhaps a cache problem of firefox.
Yeah sorry I fixed it in my local build only for now.
About the video:
I noticed that you 'killed' faces, is that with the smooth tool or what exactly? I had the issue before with NaN heights but I fixed it right before release 3..
handy solution to fix the height of those 2 sections.
Yeah the smooth tool is now the de-facto standard for fixing the mismatching heights of new tiles..

EDIT:
Known Issues List1. Undo: If you drag your mouse from one tile to another while editing in terrain mode, the undo will only restore the first tile you clicked on.
2. Undo: Undo does not properly update the heights of entities raised by the raise tool
3. Rendering: Transparent faces show incorrectly (Fix in progress)
4. Save/Load: Opening a world with entities on it will cause a crash
5. Linux Only: Crash because of incorrect library path.. (Fixed?)
6. Undo: Currently only supported for terrain editing
7. Texturing: Painting near edge does not paint in adjecent tile group
8. Textureset editor: null pointer crash when creating new texture
9. Save/Load: The extension is not properly appended to saved files
10. Undo: Ctrl-Z should be undo key