Users that wish to "auto" trap designs can do so in the Corel Print Window. Trapping allows shapes to "overlap" on their edges to improve registration on press.
This feature only traps filled shapes not outlines.
In Corel X5, X4 and X3 you will find the feature in the Separation Tab of the Print window. Options: include None, Auto-spreading and Fixed Width. Other options are "In-Rip trapping and overprint black".
In-Rip trapping is a pass through for some Rip software that make users manage data before releasing to a printer.
Over print black refers to CMYK separations, this feature puts colors under the black separation to increase density. Can result in a muddy, low detail print.
Other options such as "overprinting" are controlled within Corel before the print window. See document "Overprinting in Corel". Over printing is used for special effects and building under base screens.