I am not saying you don't have CP. The cracking noise on passive gliding could inidicate CP but is should be confirmed on imaging. The cracking sound may be softening and abnormalities in the smooth surface of the cartilage of the patellar cartilage but not necessarily. The IT band is continuous with the lateral patellar retinaculum and of course the IT band is continuous with two muscles at it's upper end - the tensor fascia latae and the gluteus maximus. So these muscles, the ITB band itself and the lateral retinaculum are all continuous and one or all structures could be shortened which can contribute to pullling the knee cap to the lateral side and causing tracking problems

I am not really familiar with the foam rolling technique you are talking about. Did your physio give you this to do? I couldn't comment on its effectiveness or where you should be applying it to get the best effect. However if you have any problems with this overall complex of muscles, tendon and fascia it is best if your physio sorts it out for you and gives you specific exercise.

In terms of importance - generally I am of the opinion that the strengthening and training of the VMO muscle and the overall quadriceps muscle is more important Than stretching of tight structures, but that is just an opinion