If you are upgrading from a 2.x version, your custom screens are converted automatically. However, there are a few circumstances that cannot be handled by the automatic conversion tool; you will need to recode such screens manually. For details see appendix Upgrading from Previous Versions.

If your are upgrading from a 2.x version, and you did not use full-text search in the 2.x version, you should expect an increase of approximately 30% in database size when you move to version 4.0 , where full-text search is a standard feature.