Create a new map by right clicking on the world map title located in the lower left corner. Name the shop and select the "Shop" tileset from the pull down menu.
Customize the look of your shop by adding floors, walls, windows and other elements from the "Shop" tileset, located in the upper left corner.
Select the "Event" layer. Determine player character starting position in the store by right clicking on the appropriate square and selecting "Players Starting Position."
Double click on the desired position to place the shop owner. Select the appropriate graphic to represent shop owner.
Add items available for sale in the shop by double clicking the empty white box and selecting tab number three. Click the button labeled "Shop Processing," right click that box, and select desired shop items from list. Specify price for each item.
Close the Item box by clicking "OK." Close the Event box by clicking "OK".
Save the world map. Click the "File" menu and select the "Save" option or click the "Save" button from the top menu.