Unfortunately, there has been some confusion over the initial version of the PRZM shell placed on the web site so there may be some discrepancies between the user manual and the actual program. However, no differences in results are expected.
One bug is that when defining scenarios the application button may not be available after saving a new chemical to the data base. In this instance, re-open the efate window and select ok and don't save to data base. The application button should then be available.
A problem with the option to specify bi-phasic degradation (different degradation rates before and after a specified number of days after application) has also been observed. At this time this option should be used only for single cases with parent only (that is, do not use this option when simulating multiple locations in a single series of runs or in a simulations involving metabolites.
A new shell remedying these problems will be available in 2-3 weeks.