First of all, each file must have a corresponding .info file to contain the icon information. Secondly, you can move the icons to the positions you want them in using drag and drop and the "clean up" icon positions from workbench. Thirdly you "select all" and select "snapshot" from the icons menu. Note that they will align the same each time you open the drawer but may not be a grid since AmigaOS supports various sizes of icons.