Electronic – Spice Simulation Models

You will never find an absolutely complete parts library from any vendor. What you need to do is learn how to use the library editor of your tool. There you create packages and symbols that you can place in your schematic and layout, based on the datasheets from the manufacturer.

As far as simulation goes, there is no complete/unified tool for this. You'll really only find SPICE models for basic parts, such as transistors and diodes, and sometimes for bus drivers (like pins in an fpga). You'll use a SPICE simulator for doing timing and frequency analysis for that kind of thing. For code, you'll use the simulator that usually comes with the development environment of the processor. For VHDL/Verilog, you'll need a simulator such as ModelSim for that. And for simulating transmission lines for signal integrity, there are also separate simulators that take in geometric and materials data, and also the bus driver models I mentioned before.

So the idea of simulating the whole design in one go is not really feasible, unless its scope is very narrow. What you end up doing is simulating each subsystem separately in its own suitable testbech environment, and then join everything in the pcb. Once a prototype has been manufactured, you can test, probe and debug the system as a whole.

From the LTSPice IV manual:

X. Subcircuit 
Syntax: Xxxx n1 n2 n3... <subckt name> 
[<parameter>=<expression>] 
Subcircuits allow circuitry to be defined and stored in a 
library for later retrieval by name. Below is an example of 
defining and calling a voltage divider and invoking it in a 
circuit. 
* calling a subcircuit 
* 
* This is the circuit 
X1 in out 0 divider top=9K bot=1K 
V1 in 0 pulse(0 1 0 .5m .5m 0 1m) 
* This is the subcircuit 
.subckt divider A B C 
R1 A B {top} 
R2 B C {bot} 
.ends divider 
.tran 3m 
.end 

Notice that params: never appears in the LTSpice syntax for a subcircuit call.

I am guessing that including this token in your X card has confused LTSpice about how the subcircuit should be called.