Many people ask for software on this site that is closed source (Freeware, Shareware, Commercial) and while the software is often the top of the line, Portable Apps cannot support distribution of this kind of software. So it is best to try and find an Open Source alternative for the software.
Long ago I was looking for a CD-Burning application and I literally downloaded every Open Source CD-Burning application I could Google and tested them all. And I still had not found the one I use today. In the end I found the application "Infrarecorder" by searching on this site: http://www.osalt.com/
This site lists many commercial titles and Open Source titles and cross references between them. I searched on Nero and out came "Infrarecorder" as one of the suggestions. I suggest everyone not knowing this site to check it out. As long as the list doesn't get swamped by every Open Source app and only lists the top of the line results it will be a very useful resource of finding some great Open Source titles.
BTW, "InfraRecorder Portable" has been in beta for a long time and I expect it to turn up as an official application any time. I already switched between the 'official' release to the Portable beta test version.