EDIT: the problem was in our data - sometimes we accidentaly added an empty value.
I have recently created a report using scripting (might be relevant) that calculates sum of groups based on specific criteria. While it works when I generate a report for a time window shorter than (about) 2 and half months, when the time frame is larger, the report does not generate and the error message reads "Error^Action Sequence Order:50^ERROR: There was an unspecified error loading the report. Please check your Generate Report action to ensure all fields are setup properly, and that the report loads correctly in the report designer." So far I noticed it happening for this report only, while others work fine even for large time frames. Any ideas why that might be and what could be done to fix it? Thanks!