We have run promotions over the years and there have been short term coupon codes which were used at that time that are no longer valid. It's unfortunate that there are sites out there who are basically preying off those who are searching for coupons in order to drive traffic through their site, but we don't vouch for the validity of any of them as we can't control what others are posting on their sites. Some codes are simply made up discounts, some are long expired ones. As of this moment, we don't have any official promotions running outside of those mentioned.
The only difference between the $99 standard license and the $159 developer license is that the developer license includes the Photoshop .psd files. These files are useful for web designers who may be looking to change the layout of the theme (as they contain all the size/color/layout info within them, thus saving time collating it yourself), however you can still customize the standard license theme. With the standard license you still get the theme as described on the
ClassiPress theme page and shown on the demo. If you don't have knowledge of css or don't really know what the .psd files are for, then chances are, you won't need them ;) But yes, you can upgrade at a later time if you find you need those files.
The promotion related to translation files is that if you provide us with a theme translation, we will offer you a 40% discount off your theme purchase (see the "We need your help" box of the
languages page). You don't actually pay for translation files. We use .po files to translate our themes, and members of the community provide these to us. One of our developers posted a reason why we don't auto-update languages (I'll try and find that for reference), but the fact is, we don't.
Automatic theme updates can be carried out with use of the AppThemes updater plugin which you can
read about here. Thanks.