I am trying to play [Command & Conquer 3 (CC3) Tiberium Wars](https://macintoshgarden.org/games/command-and-conquer-3-tiberium-wars), but when I download all the parts, I am not able to get it start it (not even type the serial number).
I followed two approaches, after using StuffIt Expander 16, both resulted in the error message in title.
Attempt #1:
1) Download the zip file parts 1-5 to the same folder.
2) Open the part ending in 001.
3) I was able to get "Command and Conquer 3-Tiberium Wars.dmg" and open it.
4) Drag 'n Drop the CC3 icon on the Applications.
5) Then I clicked on the "Command and Conquer 3" cion, and got a pop-up The application “Command and Conquer 3” can’t be opened".
Attempt #2 (I know that MacOS Leopard and High Sierra are different, but I am desperate):
Same, but also used CC3_Updates and CC3_NoDVDs. The former zip had a patch for MacOS Leopard, CC3_108_MAC_PATCH and CC3_109_MAC_PATCH. I tried skipping the Leopard one, and use 1.08 and 1.09 only, but it 1.08 was failing. So I used the Leopard one for 1.08 (got a warning about optimization, but worked), and then both I applied 1.09.
Then I used copied-pasted "cnc3game.dat" from "CC3_NoDVDs" to their respective locations (as described in the accompanied info.rtf) in the CC3 package, but still I received the same error.
Any help please?