In the manual (page 26) it says the maximum step length (ie, a key held) is 8 notes, is this correct? what if I want the step length to be 16, the full track length?
Uhhhh…no. You’ve got something wrong. The step length can be up to 16 units (of whatever a unit represents as determined by track speed) on the step level, plus the track scaling can take that up to a factor of 2, so 32 units.