I played the new version of IcyCraft, and sadly, survival mode seemed a bit buggy. I get no problems on creative, but survival has the following bugs:
The screen would flicker with a purple color every ~10 seconds.
I don't know how, but my inventory cleared while I was in movement lock mode. That may not be related.
Also, suggestions!
1. Activating movement lock mode shouldn't require you to move to activate it, because you aren't able to be as accurate with where you are when you want to place/break something. Movement lock should activate the other way around. If you aren't moving while pressing the key it should activate, but if you move while pressing the key, it deactivates.
2. Custom control schemes that are configurable in the program itself. You should be able to customize things like the break/place up/down keys, the movement keys, etc.
3. I've suggested this before, either you forgot about it or didn't get around to it yet. Custom background colors based on your Y layer or current chunk would be cool. If you're in an outdoors biome, the background color should be the color of the sky. The color of the sky would change with a daylight cycle. If you're in a cave, use a dark gray or black color. Each chunk could have one bit reserved to telling whether it's an outdoors (sky) or underground (dark) chunk. Hopefully I explained that well enough. Also, every once in awhile it should rain. If you're in an outdoors area, the background should be darkened slightly and a rain animation (A bunch of blue rectangles moving downwards, maybe diagonally?) should be played over it.
4. Biome smoothing. When two different biomes meet, it's easy to tell where one ends and another begins. Perhaps you could add a transition between the biomes.
Above: Smooth transition
Below: Basically what currently exists
The jump in quality did not disappoint, ignoring the bugs. The structures and biomes add to the exploration well.