Uploading it to an ftp server is stripping the file of resource forks, part of the file that tell Mac OS (from OS 9 days) that it's an application.
Adobe still uses this system because projectors have to be able to run on OS 9 as well as OS X.

You need to zip up the projector before uploading it. Control-click on the projector in Finder, choose 'Archive' (or 'Compress' depending on your OS version). Upload the zipped file instead.