
CHM Viewer can be used to quickly verify that the resulting help file contains all files and topics, you wanted.
It is essentially the same appearance as a dialog for project file selection, but it is enhanced with file preview pane and the "Save as" button.

CHM Viewer window is opened at project's Target folder place. Here you can select your resulting help file or you can choose to view another CHM help file.
By clicking on "Save as" button, you can save the selected file (no matter if it is from CHM archive, or if it is a normal file) into desired location (you will be prompted by the system file save dialog).