Jurai sorry I haven't responded to you. I'm avoiding getting into making these for others, enough projects on the go and a lack of desire to risk dealing with warranty claims etc.
They are actually quite simple to make, some basic soldering and a little bit heatshrink and most of the physical componets are done.
I'm also thinking of making up a simple cable version using a Sparkfun USB to TTL serial adapter, a component they sell for the Arduino boards
http://www.sparkfun.com/products/10008
A USB connection to the Laptop and three wires from the port on the telescope to the adapter and it should be away. If I get that done in the near future I'll post the details and outcome. That would be a cheap and simple alternative to make up.
Bob