Yongha Hwang and Sungsoon Cho from the University of Michigan have submitted a new version of the Syntax2D source code with optimizations that result in a significant speed increase in calculation (at least 5x faster).
If you are interested in trying out this new code, you can find it in the releases section. Note: It is based on the older 1.3.0.6 version.
We hope to add it to the official version of S2D in the near future.