What is your game version? I think blueprints came with a patch and your game needs to be updated to that patch to have them. Your game version should be 1.55. Check here if you need help installing it: http://answers.ea.com/t5/The-Sims-3/FAQ-Current-Patch-1-55-Manual-links-and-more/td-p/67858
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I will most likely not see your response. If no one responds to you within a few days, contact EA here: ttps://help.ea.com/contact-us/ask. For help with their website see this: http://sims3.crinrict.com/en/2012/10/how-to-contact-ea.html. It will probably be best. I hope it all works out for you - happy Simming!
