First off, I used the following tools:

• Instant Mold ($13 on Amazon) -this is used to create the molds. Just drop the strips in boiling water, carefully fish them out, and press them somewhat flat with your fingers. Very easy to use, and they are reusable.
• Green Stuff Epoxy Sealant Adhesive ($15) - this is the material that I used to make the figures. There are two tubes: one green and one blue. You cut off roughly equal amounts of each color, then rub them together until they turn a dark green. You can them squeeze the material into your mold.
• Vaseline/Qtip - used when creating each side of the mold; coat the first side (after it has cooled and thus hardened) with a light coat of vaseline to keep the two sides of the mold from sticking together. It is only used when you are initially making the mold; once the molds harden, you don't have to worry about the sides of the mold sticking to the Green Stuff.
• Base figures - in this case, I made a copy of my Microcorp Agents. According to Rocktroll, they are one of the easier squads to make...
• X-acto knife/Scissors - used for cutting Green Stuff and trimming up the finished figure.
• Small lego block - used to align the two sides of the mold.
• yodajunkie's Custom HS bases - used to base my creations.

http://i1029.photobucket.com/albums/...lev/mold-1.jpg

Now, to being the process: I brought water to boil on my stove, then dropped in a couple of sticks of the Instand Mold. Once it became soft, I scooped the sticks out with a stove-safe spoon and then molded them with my hands into one, roughly flat piece of plastic. I then placed the horizontal figure on the mold and pressed it down about half way; I also placed a small lego brick to use as a reference point when lining the molds sides together. After about 5 minutes, the mold should be nice and firm. At this point, I placed a small amount of vaseline over the mold, leaving the figure embedded. I then dropped the remaining instant mold sticks into the boiling water, repeated the above steps to extract the plastic out, then placed in on top of the figure and base mold and pressed down until I could see the figure details through the top of the mold.

http://i1029.photobucket.com/albums/...lev/mold-2.jpg

After waiting about 10 minutes, I separated the two sides of the mold and removed the figure.

http://i1029.photobucket.com/albums/...lev/mold-3.jpg

At this point, I used scissors to cut off about 1/3 of an inch of each of the tubes of Green Stuff, then kneaded them together until the material turned a consistent, dark green (a few drops of water on your fingers will keep the material from sticking to your digits). I then pressed the material evenly into one side of the mold, ensuring that all areas of the figure indentation were covered. I then lined up the top portion of the mold (using the lego piece; you can either leave in the lego piece, or remove it...But the goal is to use it as a reference point to ensure that you mold is not off slightly) and firmly squeezed it down until both molds were flush.

http://i1029.photobucket.com/albums/...lev/mold-4.jpg
(Note that I used too much Green stuff in this photo; you will generally develop a feel for how much to actually use. Unfortunately, I wasted quite a bit during my first 4 or 5 casts)

The figure takes about 8-11 hours to cure, depending on humidity and other factors. I tested the cure process by slowly peeling back one section of the top mold: if the greenstuff is still rather soft, just leave it sit for another couple of hours...Under no circumstances do you want to remove the figure too early, as you can easily distort the figure, rendering it into plastic scrap.

http://i1029.photobucket.com/albums/...lev/mold-5.jpg

Once the figure cured, I gently, slowly removed it from the mold. There was quite a bit of excess Green stuff to trim off, so I used an X-acto/hobby knife (taking extra care not to slice through my fingers!) to trim off the excess. In the end, I was left with:

http://i1029.photobucket.com/albums/...lev/mold-6.jpg
(Note: I used the original figure as a comparison during the trimming process)

After several attempts (including about 6 failed attempts, where the molds were not completely lined up, or I failed to press the mold sides flush, thus creating an overweight version of the figure), I managed to create a couple of spare squads of my Microcorp. Here is what my final, green figures look like, along with the bases:

http://i1029.photobucket.com/albums/...lev/mold-7.jpg

The next step is to glue them to the bases (most likely with superglue) and then repaint the figures.