Photoshop: Redraw issue with stamp tools

Using Trial Version, there are 2 catastrophic and probably related bugs with CS5 (Win). First is using clone stamp. It will randomly create cloned regions up to 10X size of stamp, often in shape of a stripe and in completely unrelated area of image. This is not, repeat NOT user error. It is easily possible to save the file in a corrupted or catastrophically damaged state, since the damaged area may not even be onscreen.

2nd bug is healing brush where it will create what looks like a solid line from a magic marker from brush to random part of image.

These are the only bugs I have ever seen in many years using Adobe products. I cannot purchase a standard version with software exhibiting bugs of this magnitude.