I’m a little late posting this but, there’s a new version of the CAP Demo!!! And yes, it fixes the issue with missing store content. Now you can go between CAP and The Sims 3 without the fear that your store stuff will vanish! This info was from a tweet or two by SimGuru Graham. As of the time of this post, you can ONLY get the new version via Origin. It will soon be added to both Amazon, GameStop (PC) and GameTree (Mac).
Please note that you have to UNINSTALL the Demo before you can download and install the new version. Also note that you do NOT re-add Twallan’s jailbreak Mod as it will not be compatible.