You probably just clicked on the folder... Try clicking the zip file you created once, and then click "open" on the window that browses for the files to select that file. When you click on the zip, does the file really have a ".zip" behind it?
Also give winrar a go, instead of compressing the files to a zip, you compress it to a rar. There are various other formats, if you are using LINUX, try jar, war, tar, tar.gz, 7z, ar, tar.izma, or cbz.
Also note when clicking "post message" that it will take a while to upload the file before the page refreshes again. Make sure at the bottom left of you firefox browser it says "sending request" or "waiting for ...". If it says "Done" or "stopped" after clicking post, and your post isn't there, something is wrong.
TheComet
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