Inserts a DoubleCAD (or other CAD format) file into the current drawing.

Select the type of file you want to import from the List Files of the Type drop-down list. See Importing and Exporting Files.
The complete contents of the file will be inserted into your drawing, alongside any existing objects. If the inserted file contains blocks, the Add Blocks window will appear (see Inserting a Block.)

Note: The contents of the inserted file are embedded, not linked. See Inserting an OLE Object.

Inserting Partial Data from a File

The right side of the Open window contains a box in which you can select what you want to add from the selected file.

For example, you can insert all objects ("graphics") but omit their properties or line style. Or you could insert a file's layers without the objects that they contain.
You can use File / Extract To to save only selected components in your drawing to a *.tcw file. This is useful for creating file templates.
*Override data:* If any items with the same name are found in the target file, they will be replaced by the items in the source file.
*M, then Properties will also be selected.