Here's a better way to play Starcraft 2 Single Player even without a BNET account.
Using this crack you'll be able to load SC2Map/SC2Replay files without having a license.
Follow the instructions carefully.
This crack assumes that you already downloaded and installed Starcarft2 Full Client which includes the Single Player Campaign.
Visit SC2 Full Client download.
1. Download Base15405retail_enGB_Crk.rar. THIS IS for the enGB version
2. Extract content to any folder
3. Go to StarCraft II\Versions\Base15405\ and rename SC2.exe to orig.SC2.exe
4. Copy SC2.exe into StarCraft II\Versions\Base15405
This crack unlocks the ability to load SC2Map/SC2Replay files without having a Battle.Net account (aka License).
You'll have to extract the Campaign maps, so someone go and write a tutorial or a batch file to do this task!
Here is a better way to LOAD your progress. (No need of save/loads)
Simple, instead of starting SC2 automatically.
Go to Documents\Starcraft II\Saves and double click the file called LibertyCampaignSave. Now the game will boot exactly where you were in the campaign, just like it would normally do.
(btw, it can be in "My Documents" folder as well).