Towing Issues: Vehicle towed for registration issue (actually smog check), vehicle registration fee, smog certification

Question
A couple hours ago i was pulled over while driving in San Francisco. My vehicles tags were expired, although I did pay my registration on time earlier this year as I verified after getting home and looking at my bank statement online. The officer ended up issuing me a fix-it ticket (no big deal) and then impounded my vehicle (a really big deal because the DMV isn't open again for another 5 days do to Thanksgiving and gov't furloughs). Obviously I'm not happy about this knowing that I paid my registration, and that its going to cost me in the neighborhood of $500 and my entire day next monday to clear this up with the DMV. After doing some further investigation, it turns out that my vehicle was due for smog certification earlier this year. The CA DMV site says this: "you will not receive your new registration or year sticker until the smog information has been received by DMV". So, according to the officer who cited me, after 6 months they have to impound my car. So, I clearly missed a step by not getting my vehicle checked, but i don't recall ever getting any information from the DMV after I paid them that I needed a smog check. In California cars don't need a smog check until the 7th year after the model year of my car, so this was effectively the first year it was required for me.

Having spoken with a different police officer, it appears that my only recourse here is to take it up with the DMV and get them to admit fault (fat chance). My question is this: If I pay my vehicle registration fee and they issue me a receipt (which they did), is my vehicle considered 'registered' for the purposes of being on the road? It seems like this a steep price to pay for a smog check related issue on a '03 honda which was barely out of compliance AND owned by someone who had paid the registration fee. I'm hoping at minimum for leniency from the court administrator and not have to pay all the towing and storage fees for this 4 day weekend coming up. Any advice you can provide will be appreciated!

Answer
Technically the vehicle is registered once you have a receipt, however it is improper display of a tag if the decals are not on the tag. This is a very trivial point. The smog check is an actuality though, and must be in compliance in most states. Your best bet is to approach the DMV with a very polite and professional demeanor and ask if they can help you.