Download here the Sunrad module of the ESR.pack. This sunrad package is the new 0.94 version with improved routines for Cloud Screening for Prede, including a correction on the air pressure estimation in case pressure measurements are not available. Reference on the software: Estelles et al., 2012. Other improvements in the gas absorption algorithms, water vapor retrieval, and estimation of the retrieval uncertainty will be later provided in a new sunrad version.
The Skyrad pack version 4.2 can be downloaded from this link