Getting Started with Split & Combine Plugin
Split & Combine plugin allows you to easily divide large file to as many parts as you need or to parts with specified maximal size (e.g. for transfer on removable media - CD/DVD/floppies). Later you can join all parts back to original file and check the resulting file for transfer errors (using CRC checksum). It can be done using this plugin or using simple batch file (special .bat file is prepared when splitting file; you cannot test CRC checksum using batch file).
See Menu Extension section in Using Plugins for a description of basic work with menu extension.