How to insert another sh3d file as a new level?

[species5618w]

Is there a way to insert another sh3d file as a new level? I tried to select All-copy, but it wouldn't let me paste.

[hansmex]

This should work:
- open an empty instance of SH3D or a file that functions as the target
- open the source file, select everything with CTRL-A, copy it with CTRL-C, deselect everything
- switch to the target, create a new level, use CTRL-V to paste your source file

Hans