Because with internal Portal, the boxes are catching at least EIT p/f Information after/during zapping if the stream contains PID18dec with the TV Service. But not if you use the Ministra, the EPG data from the stream is ignored. To fetch XMLTV conform Information from external sources there are often incompatibilities with XMLTV Tools. An Importing from epg data files done from http://www.webgrabplus.com/

would be great. Even importing from TVheadend would be good - maybe an Interface between them.