Adobe thinks it's got to keep "improving" its products but it winds up making them worse. IMO.
The reason why you had to buy newer software was because you bought a newer computer. Blame Apple too. Your iMac has a different processor than your G4. Adobe had to write new software for it.
One can still buy second-hand Macs. You could have probably found a replacement G4 for under $200.
Fooey on silly consumer choices and expecting nothing to change in computing in a decade.
CS 4 is ancient software in computer years. The most recent version is CS 5.5. Where did you find an authorized reseller to get a copy of CS 4?
CS 4, 5, and 5.5 all offer advances compared to the versions they replaced. For some the advances of minimal and a user will skip it. For others the advances are real time savers. If Adobe did not offer new capabilities and charged the same amount of money for software that merely ran on a newer computers, then you would be really angry.
As inconvenient as the process may be at times, overall I am inclined to suggest staying somewhat current with software that you use on a regular basis. You don't need to jump to every upgrade that comes along, but the longer you wait, the more effort is required to adapt to changes. It is just easier to make smaller batches of incremental changes over time, than struggle through a lot of them at once.
Sorry to hear about your G4, but invest a little time into learning your new iMac and software and you will gain a LOT in return; more creative options, better productivity, more processing power, and features/options that simply didn't exist with your older hardware and software. Software/hardware upgrades force users to adapt, but rather than seeing it as a "pain", think of this as an opportunity to grow, learn and be inspired to do more. Let that be your silver lining.
3 to 6 months from now, you'll likely look back on this and ask yourself why you didn't upgrade sooner. Maybe you'll even find a use for the "blob brush".
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