I'm stumped, but then, I'm not the developer... Razi is. Let's see what he says, and whether he can find a possible explanation to such a one-in-a-million phenomenon !
In the meanwhile, here's a suggestion for further investigations using an experimental approach, plus a possible "workaround":
1/ reload from your most recent "good" save (which, as I understand it, is NOT in the Dwarves World)
2/ do a few things around, whatever, and save in that very same world , and then check whether that new save file is still good. This is to confirm that only saves in the Dwarf World are corrupted (I'm not sure you have been definite about this)
3/ keep doing a few things, anything, walking around, and quit the game WITHOUT SAVING. Then, relaunch the game by selecting "Return to the current game". I'd like to make sure this automatic save is still working...
4/ Then, move on to the Dwarves World, and do those same experiments BEFORE laying the pipes. If the save files work, we will have narrowed down the problem a bit.
5/ And then, try again saving (and checking the "automatic save") AFTER laying the pipes. If the automatic save works, fine, you will be able to progress again in the game, and give time to Razi to find what it's all about !
Let's hope we get a better view that way. So far, the pipe-laying is only a potential suspect, but as you know, coincidences happen, simultaneity does not necessarily mean causality, etc.
Well, this is a sort of great puzzle within the game, this "saving" problem, don't you think?
