I have two different gaming rigs and have always used the steam cloud save feature to synchronise progress between the two. Apart from the general wonkyness of steam cloud itself, i have not experienced many issues but i think something went wrong with the 1.0 Update.
Steam cloud succsessfully downloaded the saves from my primary PC to my secondary PC over Steam cloud to: Documents/MyGames/Into the Radius 2/Profile 1/Single but the saves dont show up ingame.
I tried deleting the files and re-downloading them. I tried deleting the pre-1.0 files but they get readded on startup. The only thing that worked is starting a new game with Profile 2 and manually adding all the savefiles from Profile 1.
I will do a backup of my primary save manually just in case but that seems to be a workaround for now.