So I return here, after 2, almost 3 years. TL;DR, I never ended up getting in-game. I'm just listing on what i found out and I'm asking for help.
I thought that maybe by swapping EXE files, i'd get somewhere. Turns out nope. Swapping the exe file in the main directory changed absolutely nothing.
Then, after scourging through folders, the folder RetailExe told me the answer why that didn't work. In that directory lies the
actual game executable, ra3game.dat. Then I realized I kind of knew this with C&C 3 and then realized the file structure with c&c3 and ra3 beta is the same. But anyways...
It was all cool and games finding this tid-bit out but... I had no other ra3game.dat's to swap around and potentially create a frankenstein out of this. Then I started looking on how the retail version launches and it had vastly different file structure compared to the beta.
Everything was just thrown into one folder (except for the .exe, support and launcher folder) and called it a day. However this also meant that there was no ra3game.dat. Or was there...?
I accidentally found out today, that .game files (like ra3_1.0.game, ra3_1.1.game etc.) are actually disguised .dat files. .dat files on the other hand are just .exe files. That last part might not surprise someone but it certainly surprised me. So I started swapping things around, however still nothing worked.
The only choices I have left, are to somehow bypass the EA Authentication server, or find a working key (or bruteforce it somehow). And here's my cry for help. I don't know if someone's willing to just crack the beta (very unlikely), buuuut.....
I gave my CD key away as part of a competition we had on Digiex back in the day.
You say you gave a key away to someone and my obvious question is, do you still have it somewhere? Reason I'm asking is that, to my knowledge, those keys could be used multiple times before being deactivated for being used too many times, and unless that person you gave it to installed his copy on every computer he had, there are still some uses left.
Of course i also must face the possibility that all of the keys were deactivated, although i think there would be a different error message for that like for example:
"GL:5575="Thank you for your interest in this game; however, the trial period for this game has ended. To continue playing, please purchase the full version.”"
It's possible that they also just made all of the keys invalid but i dunno. Still worth a try if you don't really know.