There are two factors that you want to keep in mind when you are trying to create a naturalistic blending of two or more colors.
In the example above the main color was digitized using a .40 mm or 4 embroidery points space between stitches, on the overlapping colors we increased the space to
.90 mm which decreased the density by more than half. This creates a smoother transition and keeps the combination of densities from getting too dense.
You also want to make sure that you keep all of your stitches as parallel as possible so that the colors will blend together and not appear to be separate shapes or objects.
Blending colors together to increase the three dimensionality of your designs is easy if you just stick to these two factors; density and direction.

In addition to creating your own fill patterns and motifs KPD compositions also allows you to create your own custom fonts. you can use an existing true Type font or create your own font from scratch. All you need to do is to save all of your letters (named to correspond to their Character Map name as 1=0031)in a folder called whatever you wish the font to be called. Save them as .lbf format files, then place the folder on your c drive in programs/KPD/fonts/characters.
You can then press shift+ctrl=F and generate the font. Now you are able to use it just as you would any other font in your program.
This is a great way to increase you available font selection at your leisure and all it costs is a little of your time.

As with the other two stitch types, runs and satins, fill stitches may be manipulated very easily to create exciting new textures and effects.
Standard Fill
When you choose fill stitch you will automatically be in standard fill mode, this is the most popular fill style used. It consists of a pattern of parallel running stitches that are alternated in a predetermined pattern based upon the offset of each row of stitches to the preceding row. It is calculated in a similar fashion to laying rows of bricks. This stitch type allows you to change the density and stitch length to vary the look of the fill
Emboss Fill
The emboss fill derives it's pattern from a shape that is essentially embossed into the fill. Wherever the running stitches in the fill intersect with the image transposed onto it the needle will come down and make a stitch, so this fill pattern consists of many different stitch lengths based upon where the image and running stitches meet.
Motif Fill
The motif fill replaces the running stitches in the fill with a digitized design, which can consist of running or satin stitches. This is a great way to add a lacy effect to your designs and at the same time reduce your stitch count.
Please be aware that you can create your own patterns for both the emboss and motif fills so that you can customize them with the texture or even logo you are digitizing.
Fill stitches, of course, are used predominantly to fill large area of stitching in your designs, so why not take advantage of this large portion of your designs, by experimenting with all of the textures and effects that can be achieved by manipulating your fill properties.

Satin stitches are, in my mind, the most versatile of stitch types at an embroidery designer's disposal. They can be one throw across, patterned, or be converted to a contour stitch. The nicest feature of this stitch type is that you can control and manipulate the stitch directions throughout the shape to add more life and movement.
The most impact is achieved with a true single throw satin stitch, as this will reflect the most amount of light and truly stand out against the rest of the stitch types in a designs. Sometimes however the area you need to cover is wider than a single throw will practically reach, so you really have to divide up the stitches, and you have many choices as to how you do that.
Standard pattern
The simplest way to divide up the stitches in your satin column is to apply a pattern, this can include something as simple as a random fill to the more defines corn row pattern. You can also make the stitching in each one of the patterns longer to impart more sheen or shorter to make the pattern more pronounced.
Embossed pattern
If you choose an embossed pattern you can give it a more defined texture, you can even choose your own motif to carve out of the pattern.
Contour
Opting for a contour fill can totally change the entire personality of the stitch. You can transform a silky satin stitch to a very patterned and snaky combination of undulating running stitches.
Whatever you choose be aware that you can apply just about any personality to a simple satin stitch, with the switch of a few property options.

When you use any automatic function you are relying on the quality of the artwork. There are two types of artwork, you can choose from, they are vector or raster.
The vector types you can choose from are .ai, .emf, .eps, .wmf, .dxf, and .plt.
The raster types just about any bitmap file including .pdfs.
The quality of the images is going to control the quality of your finished embroidery. This is especially true of the raster files. You want to make sure that they are 300 dpi if possible and that they are at least the size of the finished embroidery.
You can use the auto-digiting wizard to completely automate the digitizing process, use the magic want to auto-trace the elements of you designs and then introduce the stitch type and direction, or you can manually digitize the entire design. Whichever method you choose it is always beneficial to make sure that your artwork is as clean as possible before you start.

Although we only have three basic stitch types to choose when creating and embroidered design, if we take advantage of all of the different property choices available, we can transform those stitch types into an almost unlimited amount of embroidery effects.
I would like to start with running stitches.
A running stitch can easily be transformed into a double or triple (bean), but can also be converted into a row of symbols or motifs, and the size of each is controlled by the stitch length of your original running stitches. If you lengthen the stitch length you increase the size of each of the symbols or motifs. The difference between motifs and symbols is that symbols can be any combination of stitch types and can be custom digitized by you to recreate any shape or object you wish to add to your design. Motifs are comprised of running stitches and are also can be custom digitized by you to recreate any shape or object you wish to add to your design.
The next two entries will expand these ideas to include Satin Stitches and Fill Stitches.

We all know that you can choose to digitize a design either automatically, semi-automatically or choose to tackle the design manually, but did you know that there are a lot more decisions, some obvious and some a little more subtle. I figured that I would jot some down, and share them with you.
Here they are in no particular order.

Minimizing the details
You can only put so much detail in a design before it becomes indistinguishable.
Also including too many details will also cause thread breaks and bird nesting, because there is a limit as to how many stitches can be placed in any given area.
To pare down details try tracing the details on tracing paper with a pencil. The width of an unsharpened pencil will roughly equal the width of a bean stitch.
In the very least turn 3-D view on and view it at 1:1 ratio before you sew it out, if the detail looks good you are fairly safe that the design will also. Another thing to look for is short stitches, they are also a source of thread breaks.

Overcoming fabric types,textures and patterns
Use underlay to stabilize the design, always start with an overall running stitch underlay on stretch or slippery fabrics.

To use underlay to flatten the texture of knits such as pique, place a zig zag underlay under satins and a lattice underlay under fills.
Also use lattice underlay under fills when sewing on velvet, corduroy, and fleece.
Use edge walk running stitches under columns when sewing on twill
When sewing on caps, start in the middle and work our way out alternately from side to side. Place your underlay as you digitize each piece.
Overlapping
Always overlap the first color and then place the second color on the dividing line. If you rely on pull compensation to make your stitches overlap you lose control of the exact point where they meet.
Blending
You can either choose to blend colors by using a gradient density or by overlapping fills or satin stitches.
When using either of these methods you want to keep the stitches as close to parallel as possible, so they will blend and not separate.
Lettering for foam
By placing satin stitch at the end of each column, you can be assured that the ends of the column stitches will be perforated and the edges will be hidden.
The few random thoughts were meant to get you to think about why some embroidery problems occur and to help cut them off at the pass.