Try something out to compose a relative folderpath ...
_volume .................: %_volume%
_parent_directory .......: %_parent_directory%
_workingdir .............: %_workingdir%
_workingpath ............: %_workingpath%
_path ...................: %_path%
_folderpath .............: %_folderpath%
depth_path .............: $folderdepth(%_folderpath%)
_folderpath_rel .........: %_folderpath_rel%
depth_path_rel .........: $folderdepth(%_folderpath_rel%)
_directory ..............: %_directory%
DD.20090802.1415.CEST