Email your save to support@larian.com, with a description of the problem. This happened to me, as well (getting knocked back during combat), but I saved before climbing the ladder, so just reloaded when I couldn't get back in. Larian has edited the character location for a couple other people to put them back inside the bunker, and presumably this will be fixed in the next patch (expected about or before the release of FoV and DKS).

Help...cant get to levers to lower force shields



In XP the saves are in the folder

C:\Documents and Settings\ %username% \Local Settings\Application Data\Divinity 2\Savegames


or in Vista / Win 7

C:\Users\ %username% \AppData\Local\Divinity 2\Savegames


You may need to set Windows Explorer to show hidden files and folders (XP, Vista, Win 7).