It seems that the full ubuntu1204-V1-full.zip file is corrupt on my ftp server (and maybe source forge but not sure on this one). This is likely due to my slow upload speed to my ftp server (about 125kb/s) meaning it takes along time to upload and gives plenty of room for corruption.
Well along with the release of the new images I have started to create torrent downloads for my files instead, which will prevent the problem of corrupt along with giving faster download rates, and a nice way for people to support the project by seeding the images.
In the next paid apps updates torrents will be included as a download option (There are a few good torrent clients for android or you could just use the torrent file to download from a computer).
But for now if you are having this issue of corrupt downloads head over to the download page on this blog and you will find links for the torrent files :)