Actually, you can use your current updates, assuming you have another computer, a spare Hard Drive, or a CD-RW.
Here's what you do.
(1) On your current computer, install Photoshop 5, then upgrade to Photoshop 7.
(2) Locate all the Photoshop files (help menus, any customs, the Photoshop 7 folder) and save them to another computer, a spare Hard Drive, or a CD-RW.
If you use a CD-RW, after you copy all the Photoshop files to a spare disk, save the disk, and don't lose it. When you get your new computer, upload the files on the disk to the
same place on your Hard Drive as the files following step (1).
If you use another Hard Drive, simply transfer the files over, and don't earse the drive. When transferring the files back to your new computer, place them in the same place as the files following step (1).
The same goes for computer to computer, except you will need Firewire Target Disk mode.
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