LTspice darlington model
So I assume I cannot just copy this into standart.bjt file.


You can copy one line models that are based off of the npn or pnp spice model such as this:

.model kt3102e npn bf=5000 br=5 is=.2p tf=.4n cjc=12p cje=12p vaf=100 tr=45n rc=.5 rb=1.5k rbm=80 irb=10u ikf=50m xcjc=0.3 kf=5f eg=1.11 ne=1.35 ise=0.1p nc=2 isc=1p Vceo=20 Icrating=100m mfg=USSR 

so you could copy this into the bjt file (but that isn't legal without obtaining permission):

.MODEL TIP41C  NPN (  IS=290.83E-15 BF=113.55 VAF=100 IKF=1.9905 ISE=1.3946E-12 NE=1.4763 BR=.1001 VAR=100 IKR=10.010E-3 ISC=320.65E-12


+ NC=1.8994 NK=.58929 RB=.71129 CJE=348.44E-12 VJE=.78228 MJE=.42865 CJC=184.26E-12 VJC=.47897 MJC=.40458 TF=36.381E-9 XTF=100.32 VTF=21.563 ITF=28.791 TR=10.000E-9  )

So the tIP41C works in the .bjt file, but sub-circuit files don't work (files with more than one spice line as far as I'm aware) so the bd680  won't work in the .bjt file.

Either file can be imported by using the include statement:

.include C:\Whatever path\LTspiceXVII\SQ7414ENb_PS.lib

Then finding an existing model (this works for any model) and pressing alt and clicking, you should get a menu like this. Change the type prefix to X and the spice line to the model in the include file



More complete description on this here: 
http://ltwiki.org/LTspiceHelpXVII/LTspiceHelp/html/Third_party_Model.htm