I had a frustrating experience with CAW once too. I can't build from scratch very well, but I love to decorate! I was editing an empty custom world made by another person to suit my own purposes. I just added more available empty lots and of different sizes. Then I added completely decorated lots and filled up the whole town, but when I tried to play it, there were too many routing problems. No sim in the town could pass through any doorway and I spent a real life week, every day after work, going to different lots, trying to figure the problem out.
Once I did, I realized that I no longer had functional versions of those lots saved anywhere. I had to scour the internet to find the lots I'd downloaded and edit them to my tastes all over again. Then I had to redownload that custom world and edit it all over again. Lastly, I exported the edited world with all empty lots and then added each decorated lot manually in edit town mode in game.
It took my months to do this. I was livid!
But... the new version of the edited world was actually so much better. There are no more town-wide routing failures and I had a ton of new ideas to improve upon my original town design. Even though I hated it at the time, it was worth it! :)