The previous compare value is repeated if the PWM period is shorter than the time it takes for the EasyDMA to retrieve from RAM and update the internal compare registers. This is to ensure a glitch-free operation even for very short PWM periods.
Only SEQ[1] can trigger the LOOPSDONE event upon completion, not SEQ[0]. This requires looping to be enabled (LOOP > 0) and SEQ[1].MAXCNT > 0 when sequence playback starts.