ModEnc is currently in Maintenance Mode: Changes could occur at any given moment, without advance warning.
PreviewPack
This page should correctly be named "[PreviewPack]"; it is wrong due to technical restrictions.
This section in a map file contains a base64-encoded string of LZO compressed data that, when decompressed, represents the picture that is to be used as the map preview.
There is little need to edit this manually, as XCC Mixer can create this section from any desired picture, which can then be pasted into a map file. This is used in the newest version of the Assault Mappacks to display an informational picture to users which are playing an Assault-compatible mod without downloading the mappacks themselves. (See the Assault Mappacks page for more info.)