How are programs assigned?

I haven't used my MPC Live in a long time, and only ever scratched the surface with it.

My current question is very basic - How does the MPC Live assign programs to program slots? I find this to be confusing when browsing around the MPC. Possibly the slot a program ends up in doesn't affect anything, or is never referenced?

I made a quick sequence using Tubesynth. Then a bassline using bassline, then added another melody into Tubesynth using a new midi track, but same program, then I added some drums, and when I went to the channel mixer, which was set to view Programs, I was expecting to see 3 programs, but there were 6, including a clip program, which I hadn't used. Slots 5 and 6 were empty? but 7 and 8 were used.

So I added another plug-in program to see where it would be added, and that got thrown into slot 9, not the next empty slot 5.

Is there logic to what the MPC is doing?
Am I somehow advancing the program slots without knowing?

S.

The 'slots' fill up in the order you add programs to a project. The first program you make is going to be the first one, the second one will be number 2, etc.. They have their place whether you are using them in the project or not. You can have a 3 track song, with 20 programs open, and even though you're only using 3 of them, you're going to see all 20 of them in the mixer.

The blank ones you see in the Program Mixer page are usually MIDI only tracks. I have no idea why it puts those in the Program Mixer as well, they're all in the MIDI page too. I have honestly never used a Plugin in the standalone MPC so I have no idea if those show up blank but that sounds like what it might be. I usually go in when a project is 'finished' and reorganize my stuff since my programs are usually way out of whack with the track lineup by the time Im done. I just delete all the programs from the project, then add them back in directly from the project folder in the order I want them to show up in the mixer. That way all my actual programs show up first in the mixer, and all those blank MIDI tracks that play my hardware gear get moved to the end of the list.

Oh yeah, I see, it makes a blank project for CV and every program type, even though I'm not using them, and don't even have CV on my machine. Thank's for the tip.