Rex informed us that the installer information in the .aiu file (e.g., size and MD5) is not guaranteed (though thus far it has always been correct), effectively saying "download it; try to install it; if not correct, it cannot be installed". Due to the download volume limit my ISP inflicts on me (speed reduced to less than 100kb/s if over the limit) I download using a batch file, and copy to all licensed systems manually.