The documentation has yet to be updated for all products to refer to the Preset Manager rather than the layout manager. So the Preset manager is the correct location to add new layouts.
You should be importing the entire downloaded zip file for the EMS bases layouts. Once you import this zip you should have an EMS version of each of the layouts listed.
Once you have successfully imported the layouts you can create a new page based on these that will use EMS bases settings for text, line height and some others, here is an example of the output directly from the CSS:
This came from creating a page from the 1 column, elastic, centered - EMS text using the cabo sunset color choice. This test was performed with CSS Sculptor v3.0.0 in DW CS3 on an XP machine.