Here are a few more examples of bugs:
When rendering auto-stretched items with sloped SMs, timing is inaccurate if the SMs are spaced far apart. The same actually happens with manual SMs. Interestingly, however, manual SMs lose timing at towards the end of the stretch segment, whereas auto-SMs lose timing at the start. In this image, the auto-stretched item is on the left, and the manually stretch item is on the right. The rendered takes are at the bottom:
If there isn't a tempo marker precisely at the start of the item, the segment slopes are incorrectly interpolated:
