Help PLEASE!

I am running MS 2.2 on a linux server
Installed paypal ipn 2.8.

I have it all working ok except the download. and they are driving me crazy.

First the way it is setup "NO-ONE" can find the link, VERY POOR design. I NEED to change how this link appears to them. I did ad some text to the download links header telling them the link should be below, but it has not helped. Still a LINK should look like a LINK, not just a piece of text in a table.

Second Sometimes the link is dead. even though they have paid. order status says processing.

Third Sometimes the link just does not start downloading.

Fourth On a mac system the filename and extension are not correct (If the link is active). Even though with 2 cents of brains they can just drop it on stuffit expander and it unstuffs fine. The latest was from Mac OSX with tried to open it as a PDF.

Fifth Download by redirect - why do I want to use this. What is the most compatible way to setup

Download directory and Pub directory are set to 777

I have read and read with very little to help.

Please can someone help me get this fixed????????????????