PixelSugar v3.0 and later can read the .rls recipe format used by RadLab. Here's how:
1. Let PixelSugar import them for you
The first time you run PixelSugar v3.0 or later, the app will look for RadLab recipes already installed on your computer. Simply choose to import RadLab recipes when prompted.
2. Manually Import
Go to File -> Import Recipe and select the .rls file(s) you'd like to import.