I never saw that particular issue, unless it is lag. Dirt, sand, and gravel can move in Freeminer, so try building on a solid foundation of stone. Of course, you can also live underground, as you can go very, very deep. For the time being, making sure that the weather checkbox is unchecked is a good idea. Unchecking the real liquid checkbox might help too. Did you try all three of the mapgens that come with the game? How about one of the servers?
If those options fail you, try Minetest instead (what Freeminer was forked from.) When version 0.4.10 comes out, there will be a couple of new 
subgames for it, in addition to the default 
one (I advise going with the new subgames, as the default one can be boring without mods.) To find the latest development version of Minetest for Windows, follow the following link:
https://forum.minete...ewforum.php?f=3
Seek the latest development version by either Fess, sfan5, or BlockMen (as of now, they all provide 64-bit builds.) For OS X users, check out Morn76's development builds. For people that use Linux and Ubuntu distros, there are scripts that make Minetest builds for them in the forums.
Concerning the new subgames, below are links to two of them:
https://forum.minete...php?f=15&t=9066-Minetest NeXt
https://forum.minete...php?f=15&t=9033-Carbone
Please, kindly try them out and post what you think of them here (or in the Minetest forums.) Most mods should be compatible with them. On an interesting note, these two subgames also work in Freeminer, so choose them if you don't want to have to deal with flowing dirt/sand/gravel (I 
sure don't.) To use them, put them in the games folder and select one of them when starting a new game.
Edited by Nolornbon, 09 May 2014 - 09:55 PM.
