@jfalcom -- I do realize the differences between live traffic and recordings. The example links I provided above demonstrated a live feed from ARRL W1AW code bulletin on 12/24 at 3.58105 MHz that I decoded using experimental version of FLDIGI v3.21.75 connected via SignaLink USB to Elecraft KX3 radio.
However, there is a difference between debugging software and listening live feeds. I posted this question to figure out ways how to get a test set of boundary conditions captured by other hams so that I could re-run those errors in a controlled environment to replicate observed software bugs & decoding errors. Trying to debug a live feed is very hard and unfortunately beyond my skill level.
My goal is obviously to make the software to work well with a real source and be capable to self-adjust automatically to different band conditions, operators and traffic styles. Your proposal on listening straight key nights is actually a real good suggestion -- those events are the opportunity to see the real human variety of hand keyed Morse code. Thanks for your suggestion.