As previously stated, the config directory contains all of your settings; however, some of those may contain paths. So, unless your two computers are set up identically, copying the config directory from one computer to another may not work, as you have seen.
Using the import/export capability is the safest way to migrate settings from one computer to another. There may be some settings that are not handled with this mechanism, but I think they are almost all there (if not, indeed, all there). This feature was not set up to migrate settings from one OS to another. So, you may still have some issues if you migrate settings from Windows to Linux, for example.