One of the nicest features of the Software Updater is the automated option to remove a previous kernel immediately after a new kernel update. However, at this point the Software Updater could be a little confusing for some users. Which I've found to be the case with my relatives.
Specifically, the title "Updated Software is available for this computer. Do you want to install it now?", and the button at the bottom right which you use to remove the software is still labelled Install Now. Also, each item in the list of software is accompanied by a 0Kb under a Download column.
Maybe the next release of Zorin could add a little polish to the Updater to remove any potential confusion.