The only way I got round the "Read Only" properties problem in Win 98 (following excellent advice from this forum) was to use Stuffit to make a self-extracting archive of my entire solution folder. Launching this from the CD forces the user to unstuff the folder to their hard drive (anywhere they choose). The result is that the properties of all files within the folder are intact (i.e. NOT Read Only).
On the Mac side, it's amazing how many people try to run the solution directly from the CD, completely ignoring instructions telling them not to. So it's probably advisable to use Stuffit for the Mac as well, thereby forcing users to copy the files to their hard drive before they can use the solution.