LTSpice, MAC97A8 TRIAC model, Vgs error
From the LTSPice IV manual:

X. Subcircuit 
Syntax: Xxxx n1 n2 n3... &lt;subckt name&gt; 
[&lt;parameter&gt;=&lt;expression&gt;] 
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.