Ahhh if you had said Mac to start with...
For some reason i can't begin to fathom most macs don't seem to correctly support the use of The Content-Disposition Header Field, basically if your browser has the MIME type all is well however if you're local browser doesn't contain this MIME type rather than reading the Content-Disposition Header which is what its there for; the mac ignores it and re-names the file to the page name it was originally called from, now i freely confess i know next to nothing about the internal workings of the Mac OS and as i don't have one handy it makes testing a bitch still this said I do my-best to support the Mac as much as possible I've made some changes to the scripting which might help, could you please test it and let me know if you now receive the correct filename, if not I may just require all uploads to be ether zip, rar, bzip or gz files probably better for most people now i think about it.
If you find another problems please let me know as i say i try my best to support all systems but with no Mac around for de-bugging its dam difficult.
PS. Russel if i PM you a series of Links tomorrow would you try them on you're mac and let me know the results, with a bit of luck the changes I've already made should help but id still like to find out exactly why most Mac's have problems with this, professional curiosity i suppose
First person to turn this into another boring Mac VS PC thread gets kicked up the arse by me, we all know the arguments; and we all know what machines we like to use lets leave it at that.