To reinstall a fresh copy on Windows, Mac or Linux you need to follow these steps:
Backup any saved games and customised data in:
On Windows: "My Documents/tbcb2013"
On Mac: Documents/tbcb2013
On Linux: Documents/tbcb2013
Run the uninstaller to remove the game.
Delete any remaining data in:
On Windows: "My Documents/tbcb2013"
On Mac: Documents/tbcb2013
On Linux: ~/.tbcb2013
Delete any program files found in:
On Windows: "Program Files/tbcb2013"
(Might be "Program Files (x86)/tbcb2013" on 64bit PC)
On Mac: Hard Disk/tbcb2013
On Linux: /home/<user>/tbcb2013 or /opt/tbcb2013
Log into your webstore account and download the installer again.