LTSpice RF transistor 2 emitter "the instance has fewer connection terminals than the definition"
The subcircuit text shows that the two external emitter connections are simply shorted together internally via a 1mΩ resistor each.  Nodes 3 and 4 are E1 and E2 respectively, and the resultant node after connecting them together is node 35.
RE1 35 3 1E-03
RE2 35 4 1E-03

There are a few ways to handle this.  First, is to convert the subcircuit to 3 terminals so you can use a standard NPN symbol with it.  You can either ignore the 2nd emitter connection (since it's negligible) or if you want to be a stickler you can use the parallel equivalent of the two 1mΩ connections to form a single emitter that's 500µΩ.  I'll do the latter by changing the .subckt line to .SUBCKT BFP640ESD 1 2 3, change the RE1 line to RE1 35 3 500u and delete the RE2 line completely.  After those changes, the beginning of the file would look something like this:
.SUBCKT BFP640ESD 1 2 3
*
CBEPAR 22 33 2.29E-013
CBCPAR 22 11 7.095E-014
CCEPAR 11 33 2.024E-013
LB    22 20 6.623E-010
LE   33 30 1.519E-010
LC   11 10  6.522E-010
CBEPCK 20 30  4.4E-014
CBCPCK 20 10  1E-015
CCEPCK 10 30  4.4E-014
LBX    20 2 3.607E-010
LEX   30 35 5.524E-011
LCX   10 1  2.452E-010
*
RE1 35 3 500u
*
D1 33 25 M_D1
D2 41 25  M_D2
*

The final step to make this work is to ctrl+rightclick the NPN symbol in LTspice to change the &quot;Prefix&quot; field from QN to X which allows you to use it for subcircuits.


A more direct approach (which doesn't require experienced analysis of the .subckt in question) would be to use the npn4 symbol which has a 4th terminal.  It's originally meant for the substrate connection, but since you are using a .subckt instead of a .model it doesn't matter and just provides you with an extra terminal.  I will use this extra terminal as the 2nd emitter and tie them together in the schematic.  We still have to change the &quot;Prefix&quot; field as was done above.


Last is the method you hinted at in your question's comments, which is the auto-generated symbol which can be used with any .subckt.  Instead of re-explaining this, I'm just going to link to the Analog Devices website which already has a tutorial on it.