Is it possible?
I am only being able to unzip files to root directory of Documents Directory.
Yes its possible but with a trick. Build your zip file with the subdirectory you need on your Mac/PC and then zip it together with the directory structure. This will cause the unzip to replicate the same directory structure on your device. Good luck.
Yes, I am using that as work-around but don’t think it should be the correct way to do it…
Still looking for correct way of doing things with Corona SDK? 
You know better than I do its all about knowing the shortcomings and finding the right workarounds while they exist… 
Yes its possible but with a trick. Build your zip file with the subdirectory you need on your Mac/PC and then zip it together with the directory structure. This will cause the unzip to replicate the same directory structure on your device. Good luck.
Yes, I am using that as work-around but don’t think it should be the correct way to do it…
Still looking for correct way of doing things with Corona SDK?
You know better than I do its all about knowing the shortcomings and finding the right workarounds while they exist…