Sir Timid - I assure you that is not a problem due to store content. The red X's on the launcher is an indication the launcher needs fixing - and Origin is the fixer of the launcher - Origin has 3 requirements - to be installed and up to date. For you to install and keep updated Adobe Flash player and Adobe Air. Then your launcher will stay pristine and fully operational. i have almost the entire store - i have all the set - i am only missing maybe 2 dozen of the early outfits and a couple of hair style I didn't want - I have everything else ever put in that store. NO third party content though and I am very careful about the exchange. i never download anything directly to my game. I download it to a folder I keep on my desktop. Then I use a tool call custard to check the lot for third party content. If it has any, out it goes. If it comes testing clean, then I will try the lot. But I rarely go to the exchange - I have a list of Simmers I generally only download the stuff they make as none use third party content and make the most beautiful lots. As you get to know the different simmers you will learn all the lots builders who do not use third party CC. But all the store japanese stuff is great. I have it all. Just make sure your launcher is allowed to be taken care of with Origin, and you keep things updated as they are updated and you will be fine.
That problem with the launcher has actually been a problem since either Pets or Generations - I forget which, but it is probably why Origin was utilized to keep the launcher running properly and it especially needs Adobe flash player and the game up to date in order to do that.
Pretty soon Origin will be able to fix other game problems too if all goes as the Origin team intend. I know it does a good job with the launcher until you forget to check for the different updates. hehehe
Anyway - the japanese store content is good - so don't be afraid of it.
