The RAW processing application DPP (Digital Photo Professional) is a pretty good tool to work with your images. It is "free", as it comes bundled with the camera, and can even handle the specific characteristics of Canon lenses. Unfortunately it only works with Windows (and dont run properly with WINE under Linux).
But what I dont get is why Canon still bothers to add the application PhotoStitch !? The software is outdated and can handle only perfect flat images and fails the smallest challenge. It rather turn new photographers away from panorama photography. Canon should have done a OEM deal with some of the serious panorama applications, similar to the Photoshop Light Version that you found earlier bundled with scanners and cameras.
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|Stitching error (ghost problem)|