There are some excellent percussion patterns available in MIDI File Format. Zynthian offers the ability to import such files into ZynSeq sequences. Upload a standard MIDI file using webconf Library->Capture. Within Arranger highlight the sequence into which you wish to import the SMF. Select menu option Import SMF which will show a file selector looking at Zynthian's capture location. Select the required file. Each MIDI channel within the SMF will create a track in the sequence. Each track will be populated with notes from the SMF. Program changes will be added to each track. Tempo changes will be added to the sequence's timebase track. New patterns will be created as required, starting at the next available pattern above the highest populated pattern, e.g. if you have already populated patterns 1,5 & 12 then import will start populating patterns from 13, using as many patterns as required by the import. Patterns will have an appropriate quantisation level (steps per beat) to accommodate the the rhythm.