On GG (and Steam) the core and polygon updates are not needed anymore. The latest patch currently is dec13, you need to install only it.
"the optional texture patch" - I think you are talking about demo version.
Thank you for the clarification.
The optional texture patch possibly is just for the demo but it is a bit hard to tell from this link as all Operation Star patches are in one list. Not seperated for demo and full game.
http://www.graviteam.com/HELP/patches.html“Achtung Panzer: Operation Star“ (English version)
• NEW Demo (October, 30 2012)
• Core Update_GTOS_cu_v581c1_eng (May,20 2013)
• NEW Current Patch_GTOS_dec13a_eng(January,20 2014)
Polygons Update_mar_2013_eng (optional)
I found this topic to be quiet helpfull, some how missed it when I searched yesterday.
http://graviteam.com/forum/index.php?topic=11099.0Had to work late today so did not get a chance to install the game and DLC. Hopefully tomorrow night.
Cheers