StitchGenerator is a script for 3ds max that creates stitch objects and an object to illustrate the hole between stitches on selected edges, along a spline or simply by painting them. See the YouTube video for a quick overview of the features.
Two types of stitches is currently available, stitches with a round profile and a flat profile. They come in the most used thickness for the given type of stitch. The length of the stitches and the spacing between them can easily be adjusted as well as the rotation, these parameters can also be randomized to create an extra layer of realism.
When stitches are created materials for the stitches and holes is automatically created.
Get StitchGenerator here cost 29 euros for a perpetual license.