The Multi-region Exporter is a small, free standalone application that can make the process of exporting multiple audio regions in a Cubase project easier. Especially if the export process is done more than once, this application can, hopefully, save you some time and frustration.
Note, however, that if you own Cubase Pro 9 or later, you will have the built in possibility of doing audio mixdown based on cycle markers (see for example here) thus making this tool a bit less relevant.
For earlier versions, this tool is still relevant. Furthermore, this tool allows you to export regions based on audio events/parts (without cycle markers), making wave editing more simple in Cubase. And from version 2.0 you can also base the export on parts in midi tracks or instrument tracks.
The project is open source and the source code can be downloaded at the download page as well.
Note: It must be mentioned that Cubase and Steinberg have nothing to do with the development of this tool and therefore they are in no way responsible for it – its functionality / lack of functionality or for supporting it.