I have found that the easiest way to shoot a panorama is to use a tripod and to try to have no moving objects in the photo. Place your camera on the tripod and then focus and then make your settings. If you use auto focus for this then once you are finished turn it off and shoot in manual. Then you can either shoot a number of shots and pan the camera for each one while staying in one spot with the tripod or you can move the tripod in a straight line to the left or right and take your shots. If you have moving objects in the shot then it makes it more difficult to stitch the photos together using your preferred editing software. However, it is not impossible.
I would say the most important thing is to shoot each picture using the same settings (f/stop ect). Otherwise editing is nearly impossible.
I used photoshop elements for this photo. I am not familiar with Picas 3 so I can't help you with that. I did learn the hard way that I should have used a tripod. I had to do a lot of editing to stitch it together. If I remember correctly I stitched four photos together.
