The Type field is specified as "Required" (all required fields are shown in bold face). You don't have "Type" field mapping specified, therefore the tool does not let you to proceed.
If for some reson you don't have (or don't need) the "Type" field, you can change that field to "not required" by loading the ADMSettings table in ArcMap and set values in the "Required" field to zero for all records that have "Type" as their values for the "Title" field.
The ADMSetting table can be found in your Address Data Model workspace (if you already imported some data), or default ADMSettings is stored in \AddressManagementTool92\Settings\ADMSettings.mdb.
Your second question: Address Data Model stores addresses in so-called "Nickel" format, which uses only "From" and "To" house ranges, and "Side" attribute (vs. DIME, which uses "LeftFrom","LeftTo","RightFrom","RightTo").
The tool converts DIME records to Nickel - that's why you see two destination house range fields, not four.