When using the Table container "checklist" feature, doForms allows you to sort the lookup data in the first column alpha-numerically, or to present it in the same order as stored in the corresponding Lookup widget data source.  In the example below the the checklist is being sorted by the "Days" column (which is the "Lookup field" in Lookup widget). 

This sort order is accomplished by leaving the "Sort lookup list alpha-numerically" property of the Lookup widget NOT checked.