I get a warning "There are some data after the end of the payload data" when extracting an archive. What does this mean? Is the file corrupted?
It appears this is a reoccurring issue w/ 7zip. The most recent note of this that I could find is from build 16.02.
The most recent examples of this are with archives created by other archives (WinRAR, mostly), and I'm sure he'll be interested to hear of your issue with a file that was created in 7zip itself.
I recommend you bring this to Igor's attention over at SourceForge where the 7zip support forums are at: https://sourceforge.net/p/sevenzip/bugs/