because there are no updates it doesn't mean the mod is dead.
Where the heck have you been?
Life problems you know college and alot of other stuff you know.
Well as you said you can't use the new source sdk (2013) :
well yes and no.. i've planned to use the half-life 2 code to have a nice mix of things from the old and the new.
What sdk will you use and how are you going to add half-life 1 npcs?
Source sdk base 2013 community edition which will have :
cascaded shadow mapping,some great shaders and particle effects.
i will code the npcs in the game.
what about map edits?
forget the map edits.
Not anymore with half-life 2 sdk this will be a piece of cake to do.
So i assure you development will start next week.
Be wise Be safe Be Aware-Dr.Breen