Use V3 Calculations - Version 3 forms calculate client-side values in a different way; version 4 moved to a more secure method. New forms are created with this off and it is best left off. When upgrading a V3 form, try turning it off - some client-side scripting may need changing, but the gain in security is worth it.


Use V3 Form Styles - Applies version 3's styling rules to the form. As with the calculations, new forms should not need it; it is here so an upgraded form can be made to look as it did while it is being brought up to date.


If you are upgrading a V3 form to V4, it would be wise to try to turn off V3 compatibility. You may need to make changes to your client-side scripting but the gain in security is worth it.