source: https://usa.yamaha.com/files/download/other_assets/2/1192582/modx_en_rm_a0.pdf (page 83)

Velocity (Velocity Rate)
Determines how much the velocity of Arpeggio playback is offset from the original value. If the resulting
Velocity value is 0, it will be set to 1. If the resulting Velocity value is greater than 128 it will be set to 127.
Settings: 0%–200%

Gate Time (Gate Time Rate)
Determines how much the Gate Time (length) of the Arpeggio notes is offset from the original value. If the
resulting Gate Time value is 0, it will be set to 1.
Settings: 0%–200%

Arp/MS Grid (Arpeggio/Motion Sequencer Grid)
Determines the type of note that serves as the basis for the Quantize or Swing. The parameter value is
displayed in clocks.
For Motion Sequencer, this parameter value is one step length.
Settings: 60 (32nd note), 80 (16th note triplet), 120 (16th note), 160 (8th note triplet), 240 (8th note), 320 (1/4 note triplet),
480 (1/4 note)

Qntz Strength (Quantize Strength)
This parameter sets the “strength” by which note events are pulled toward the quantize beat set in “Arp/MS
Grid.” A setting of 100% produces exact timing set in “Arp/MS Grid.” A setting of 0% results in no
quantization.
Settings: 0%–100%

Unit (Part Unit Multiply)
Adjusts the Arpeggio playback time. By using this parameter, you can create a different Arpeggio from the
original one.
Settings: 50%, 66%, 75%, 100%, 133%, 150%, 200%, 266%, 300%, 400%, Common
200%: The playback time will be doubled and the tempo is halved.
100%: The normal playback time.
50%: The playback time will be halved and the tempo doubled.
Common: The value set in the Unit Multiply common to the all Parts will be applied.

Swing
Delays notes on even-numbered beats (backbeats) to produce a swing feel.
• +1 and higher: Delay the Arpeggio notes.
• -1 and lower: Advance the Arpeggio notes.
• 0: Exact timing as set by “Arpeggio/Motion Sequencer Grid” Value, resulting in no swing.
Judicious use of this setting lets you create swing rhythms and triplet feels, such as shuffle and bounce.
Settings: -120 – +120

“Velocity” - offset for the default velocities ARPs will play at. 100% = no change. 0%-99% = reduce velocity. 101%-200% = increase velocity. There are min and max "saturation" points for velocities - so minimum is 1 and maximum is 127.

“Gate Time” - Similar sort of adjustment as "velocity" except for the gate time which means how much space there is between notes. More Legato (200%) or extreme staccato (0%).

“Arp/MS Grid” - The target note to quantize to. When using swing - this will determine if the swing is 16th note swing, 8th note swing, or ...

“Quantize Strength” - amount of "slop" vs. the target quantize grid to pull in notes to perfect timing.

“Unit Multiply” - If tempo is set to 88 and your ARP timing is sync'd to tempo, then unit multiply of 100% means play the ARP at the same rate as the tempo. 50% would play the ARP back in double-time feel vs tempo (twice as fast), 200% would play the ARP back in half-time feel vs tempo (twice as slow). It's a little confusing - but the percentage represents the amount of time the ARP will take to complete playing one complete cycle of the ARP. 200% means - take twice as long to play through the ARP. And 50% means take half the time to play the entire ARP (aka double-time feel). The "double" in double-time means twice (double) the speed of tempo. The "double" in 200% unit multiply means double the duration (which is opposite of double the speed - and therein lies some confusion if you do not know what unit multiply represents).

and “Swing” - For notes that match your Arp/MS Grid value - the "odd" beats ("strong" ) of these notes will be longer and "even" beats ("weak" ) will be shorter. That's essentially what goes on here. A small positive value will give you normal expected subtle swing. Negative values will give you backwards swing with the 1st beat shorter than the 2nd. 0 is no swing.

Hi Jason,

Thanks a lot for your reply and feedback.

Cheers,
Minh