JJOS2XL help

I am reading through the osxl manual but it's pretty cryptic!
I have a few questions about some deeper functions I can't quite decifer from the manual

1 what, if any, is the benefit of using auto chromatic mode for pitched samples as opposed to using 16 levels assigned to pitch? Seems like the same outcome, what am I missing?
2 I can't understand what pattern mode does for pads or how to use it!? I guess it's a vague question but I haven't the faintest idea what the purpose is so maybe a hint would help!
3 how to use an audio track? Do people record linear audio like in a daw track? Looks like you can assign samples to an audio track, why do this as opposed to sequencing them by assigning them to pads?

4 for program change messages, do I set them on a separate pad (say b1) and when that is sequenced it will send the message to the sound module?
So you could theoretically send a sequence to a synth then change the patch back and forth while it plays back? Or would that cause to much lag?

Sorry for the long winded post but I don't need a walk through just some clarification in proper English
Thanks

1. more than 16 notes. 16 levels is just 16 notes, autocrohmatic is way more notes.

2. well least you RTFM so there is hope for you yet. Two things here, one is patterns. You can make any track a pattern, up to 200 bars total of patterns to. So now you can use this to sequence out tracks that are longer. Its like a clip of sound or midi. Now the great thing about patterns is that they can then be assigned to a PAD. This means you can make a midi CC filter sweep only, assign it to a pad and target track and the pad now sends midi loop or what ever pattern you made. Also does samples to

3. it works like a DAW yes, but if it is a long sample, it means you do not have to wait 3 minutes to get to the part you want. Its like tracking through the song and responds to set points to.

4. No because in the main screen there is a PC setting. You can use either. BUT a lot of modules/ racks might need more than just a PC command, some involve other sys ex to, so you have to read the manual of each unit to see. There is not any lag, and I do not see why you think there would be. Also some modules will have to load new patch so wont be instant, that has nothing to do with JJOS or MPC though, that is just how a lot of modules work