Hi, welcome and thank you for your question. My name is ***** ***** I am glad to assist you today.
To answer your question, NO, the upgrade will not compromise or corrupt your CS2 software. In fact, this update is necessary both for stability and security of your iMac and I highly recommend that you perform such upgrade for your IMac.
However, please make sure that you close ALL programs, or windows or applications especially your Adobe programs as and while you are doing your upgrade for a smooth upgrade process.
After the upgrade, please test all your programs especially your CS2 and they shall continue to work.
I hope that helped.
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