Check here! http://forums.steampowered.com/forums/showthread.php?t=3115691

Now that we can save progress in this, someone needs to rep up enough to unlock protector which is about rep 50 if I remember correctly. So start playing! If you are interested let someone know. Feel free to play with others so you rep up faster.

If you got ideas on how to test, feel free to share it

As the tile says, I have found a simple way that you can keep both saves seperate without even having to back anything up. Simple copy your whole Steam folder without the "steamapps" folder with your games, and then paste the whole steam folder in a seperate location. You should now have 2 identical Steam folders, but one without the "steamapps" folder. Be safe and turn off cloud sync for PAYDAY. Now, whenever you want to play version 1.0, just make sure you completely exit out of Steam, and then start the seperate Steam.exe in the new Steam folder. Essentially you are only playing V 1.0 on the Steam.exe with no "steamapps" folder, and for your everyday Steam usage, and everything else, just using the original Steam.exe you had from before. It should save the saves to seperate folders when you do this.

If you have any questions let me know and I'll try to answer them.

Keep those helmets flying! in a finally playable game - SamusDroid

We still will be LIVE and nothing bad will happen, we're just had some discussion and brought you guys great news.
It was a false alarm! :D

Thank you all for a great support