I use Debian 8.0 (Jessie), amd64 port, and kde. If I start KMPlayer and click the Open button, the default starting directory is "> Home > Documents" which refers to ~/Documents. Software on Linux systems should use ~. But if one has to use a pseudo-Windows directory, at least use ~/Videos.
Dear submitter, as the package kmplayer has just been removed from the Debian archive unstable we hereby close the associated bug reports. We are sorry that we couldn't deal with your issue properly. For details on the removal, please see https://bugs.debian.org/1110860 The version of this package that was in Debian prior to this removal can still be found using https://snapshot.debian.org/. Please note that the changes have been done on the master archive and will not propagate to any mirrors until the next dinstall run at the earliest. This message was generated automatically; if you believe that there is a problem with it please contact the archive administrators by mailing ftpmaster@ftp-master.debian.org. Debian distribution maintenance software pp. Thorsten Alteholz (the ftpmaster behind the curtain)