The KAL74 knife exists in basically two pattern, each of which is available in two versions:
patterns:
* liner lock (your third picture, with a small fuller)
* and botton release automatic (first two pictures)
colors:
* bead blasted plain edge + black handle
* Teflon coated half serrated edge + tan handle
(since those they have added a few variations like desert color and wharncliff/tanto blades).
In places were automatics are not allowed (notably the US), the automatic version is sold without spring as a button lock knife (same system except you have to open it by hand).
The knife is sold since about 3 years, maybe more.
While the knives have stayed pretty much the same, inscriptions have had slight variations over time.
As far as I know, it has always had the "automat kalashnikov 74/Pohl design" inscription. The Boker plus brand only exists since abut 2007 so previously made versions obviously couldn't be labelled as Boker plus, and was de facto "Magnum" stuff although not necessarly written on the knife.
Since Boker Plus have been created, most of the best knives from Magnum (CLB Designs, Kalashnikovs...) have been rebranded "Boker Plus", the "Magnum" tag is still in use mostly for the cheapest knives lines (price range about $15 for a smalll folder).
EDIT:
Boker doesn't sell autos in the US, but this version is available as auto where allowed, so yes, that's probably a non-us-market thing.