@Eamoex welcome to the forums!
Yes, in addition to the big reference document:
http://ucapps.de/midibox_seq_manual_m.html
there’s more documentation available, also a very nice cheatsheet has been in work by a SEQ v4+ user, it sadly was not yet published, but we’ll ask for permission to post it - for now i can highly recommend these resources to get started:
The beginner’s guide (read this first):
http://wiki.midibox.org/doku.php?id=mididocs:seq:beginners_guide:start
The step-by-step tutorials by TK:
http://ucapps.de/midibox_seq_manual_tut1.html
http://ucapps.de/midibox_seq_manual_tut2.html
http://ucapps.de/midibox_seq_manual_tut3.html
http://ucapps.de/midibox_seq_manual_tut4.html
http://ucapps.de/midibox_seq_manual_tut5.html
http://ucapps.de/midibox_seq_manual_tut6.html
These great SEQ v4+ intro tutorials by Revtor:
Will link the new SEQ v4+ cheat-sheets once we have obtained the permission from the author.
Best regards, enjoy your new SEQ v4+ and have a good weekend!
Peter