Ok, I think I managed to solve part of my problem, so I'll share my results in the hopes someone could find this useful. It would seem my old save games are screwed, but at least I got my creatures back up and running.
As to your problem downloading the C&C package, I can't be sure, but here's what I experienced. I had to uninstall everything (again) and this time, since I had a separate folder for the old C&C package (as it was a separate install at one time with it's own setup.exe in it), I had to run that manually. It complains that you need to first uninstall all the Spore stuff (which at this point I did), before it'll uninstall itself. And since I finally came to the conclusion it wasn't working properly to begin with, it was no big deal to kill the thing.
Inside the Origin client (and I see where you mentioned this, but I must not have fully understood your meaning), if you single-click on the Spore game icon in the library, and then SCROLL DOWN on the side panel that opens up for the game (something I never knew about because I don't recall seeing this before...which probably tells you a little about how much I pay attention to this thing...lol), I see this "extra content" tab down there hiding almost below the window frame (which could be the reason I didn't know of it before, because my window is too small to actually show it).
On my system, it showed as "installed" (even though it didn't work), and I'm going to suggest by now this is due to something Origin did at one time to change the install process to use this new "extra content" tab, whereas it was an independent item in the library before this. Then one day, the library icon vanishes, but since I'm not playing at that time, who cares...
Nevertheless, the client still apparently saw it as "installed", but they forced me to re-download the game, and the new game install didn't recognize this thing as actually installed, because it wasn't where it was supposed to be (it's now a sub-folder called "BP1Data" under the Spore folder, not an independent thing called "Creepy and Cute"). So, as I said, I had to uninstall everything, then manually navigate to the old C&C folder to run that setup.exe file (the local uninstall process for C&C), and THEN reinstall everything according to the client's new process. Gah!
In the end, once I got control back in my hands, the Origin client showed everything uninstalled, including C&C, and the extra content tab showed a download button for it now. I started by installing Spore, taking it one step at a time. As it turns out, I didn't need to click on the C&C download button at all. I only clicked on the main Spore download icon, and then had to accept several pages of license stuff, one of which was for the C&C, and this became an automatic install after Spore was done. I then did the galactic download after that, and now I have all my original creatures back.
Now, as to your issue of a new install on a new computer. At this point in time, the only thing that comes to mind is maybe the sequencing. The galaxy pack seems more like an expansion, so I did the base Spore game first, and the C&C followed right behind it without any further action on my part. I then did the galaxy pack, and verified everything with a test run. My creatures are happy again, and NOW I see the proper tabs on the Creator section for the C&C stuff. So unless you missed clicking on the acceptance for one or more of those licensing things (and I'll admit they don't show up very clearly for me and my tired old eyes), then maybe that caused something to fail. I personally have a habit of clicking stuff simply to get it out of my way, and if the checkbox isn't highlighted in bright neon lights, I might not see it. But I didn't need to install it separately over here Therefore, I might suggest uninstalling and trying again. Make sure you catch all the boxes and see what happens.
