In the previous version with InaSAFE 3.5 the analysis extent defaulted to the intersection of hazard and exposure layers. If this was a large area it could take an excessively long time to process. To obviate long waits we added the constraint of the view extent so you could zoom in to limit the analysis area. We also implemented a fairly arbitrary size limit above which you would be warned that the analysis area was too big.
With this upgrade we have removed the size limit. The other analysis area constraints still apply, along with the new features of aggregation layers and improved communication with the user about progress.