The des_crft_props.2da file is the .2da file that defines the options available for the add item property power. This includes specifying the item property to be added as well as the duration for which it is added and the message to be sent upon success. As with all "des_*" .2da's, this file has no hardcoded usage; it is only used in scripts. (Specifically, this file is referenced by x2_s2_addprop.) This may allow for greater customization possibilities than most other .2da's.