Having just gone through building one of these I've got a few insights.
The nice thing about using Unitrack is that you have nearly perfectly matched segment lengths. Those segments are easily insulated for building detection blocks too. They are also fairly short segments. Long enough that a loco will fit inside the block but not so long that it's going to take a long time for the loco to pass through the block and add to the time it takes for the script to complete. I built mine using the 11 3/8 radius track. This gave me 8 segments detected and so far the script takes between 22-25 min to complete per loco. If you have longer blocks, it's going to take longer for this script to finish because it is just waiting for the loco to move between the detection sections. If I had it to do again, I'd probably stick with the 19" radius track and use all 12 detection segments.
You can use any radius track you like though. The script has lengths listed for what Phil and others have used but you can easily add your own. This is what I had to do. It's just a mater of calculating the length of the detection segment in scale feet and adding it to the script file. View and edit the script file as a .txt file and then save it to the Program Files>JMRI>jython directory as a .py file. To run the script, open DecoderPro and choose Penels>Run Script and select the script to run.
When I get mine up and running successfully, I plan on doing a full write up on it.