Layers can be added or deleted by using the "Add", "New" or "Del" buttons. "Save as" provides a similar functionality to using the "ArcMap", "Google Earth" and "MapInfo" exports from ESdat.
and the button.
All standard GIS formats are supported (too many to list here). The complete list is available by clicking the "Add" button.
Raster images that do not have an associated "world" file will need to be geo-referenced. This is ideally done using a dedicated georeferencing package (an effective and cheap one is at http://www.tatukgis.com/products/AIC/aic.aspx) , or using a dedicated GIS package (Such as ArcGIS).
On the fly reprojection of data is available. Any base layers represented in Latitude/Longitude (ie most WGS84 regional and national datasets) are automatically reprojected to the maps display projection so the data overlays properly. For this to work your data must have a defined co-ordinate system in the Project Table (Access versions) or Site Table (SQL Server versions). If not you should import the basemap in the same co-ordinate system as is used for your data.
Creation of new GIS layers are supported in DXF, SHP or TAB format. For unrestricted drawing and maximum interoperability with other programs the DXF format (which is the default) is recommended.