Thank G for Murphy's Law. Don't touch your programme files. If you are on v1.69 then you should get a loading screen which invites you to pick the EPs and SPS you want to use. Tell me did you try your disk installation after using v1.69 on Origin ? If so then the disks are rendered useless after using v1.69. A lot of people have been caught out this way. If you ever want to use a disk installation, you will have to repurchase the disks making sure to get a pre 2012 base game disk. However it sounds like you are happy on v1.69. It is a lot of work but your best bet is to clear TS3 completely from your computer including CAW and reinstall digitally using Origin. I invite other CAW users to chip in with any other ideas or if i've got it wrong.
Also CAW is not a particularly user friendly tool. It is a steep learning curve which in my case involves lots of coffee and swearing. I recommend using a test world to practice and work out a plan beforehand. It doesn't matter how long it takes as long as you enjoy the process of creating. I'm sure whatever you produce will be lovely and it will be special to you because you created it. So please don't give up now :)