Looks like Samson has a privite FTP server for their legacy product manuals that is no longer easily available for pdf downloads. Look up Samson Technologies | Professional Audio Equipment
and get in contact with them for the manual. I checked on my end to see if I had the pdf and all I have is an original paper manual so if for some reason Samson doesn't help you PM me and we can see about looking something up or xeroxing what you need.
As far as spliting the signal in the mixer for recording while using it as a live mixer at the same time you will be pushing it's limits and have to get creative. The first ten channels have a send/receive insert jack post EQ that could be used but for the other six stereo channels you would have to use up some of the auxes and/or busses for that purpose (if you want to record all 16 channels separately). A common trick with that kind of single 1/4" TRS send/receive insert jack is just to put the male end in far enough into the female input jack so that the plug tip engages the female's ring (the "send" part only). That lets you split the signal, as fully inserting the male plug would break the signal path and the mixer would be expecting a "return signal". You can always do the traditional split the signals before the mixer routine too for recording and live mixing at the same time but that will require outboard pres or iso splitters and can get expensive.