I watched the video and I see you turn on "Let Ring" by clicking on it and then you start playing your tracks. I can't tell which DAW you're using, but most of them reset the MIDI controllers to their original settings on playback.
You need to add a MIDI CC event on the track you have MODO BASS on. By default, "Let Ring" is turn on and off using CC#64, also known as the Sustain Pedal.
Add a MIDI CC event to your track with the event parameter of CC64 and a value of 127. That should turn it on when the track is playing
IF "Let Ring" is turned off before playing the track. To turn it off while the track is still playing, add another CC64 event and set the value to zero.
Dave