Hjælp til Windows Post-Installer Method

Hej
Jeg bruger Windows Post-Installer Method til at køre Silent install på nogen programmer. Man kan skrive kommandoerne i selve programmet eller rette dem i config.js. Jeg forstår ikke hvorfor man kun skrive \ i selve programmet, når man skriver \\ i config.js?

Hvad gør denne linie: cond[pn]=['FileExists("%cdrom%\\Install\\DotNetFramework\\DotNetFramework1.1.exe")']

Windows Post-Installer Method
http://www.unattended.msfn.org/advanced/methods/intro.htm

//---------------------------------------------------------------------------------------------
// Reference ... prog[0] won't be used. It's just an example
// look in program.js to see explanation of these properties
//--------------------------------------------------------------------------------------------- 
// pn=0    // start value vor prog numbering
// prog[pn]=['ProgramName']
// desc[pn]=['Description']
// regb[pn]=['Registry Key Path']
// cmd1[pn]=['CommandLine 1']
// cmd2[pn]=['CommandLine 2']
// cmd3[pn]=['CommandLine 3']
// cmd4[pn]=['CommandLine 4']
// cmd5[pn]=['CommandLine 5']
// cmd6[pn]=['CommandLine 6']
// rega[pn]=['Registry Key Path']
// dflt[pn]=['no']
// forc[pn]=['false']
//  cat[pn]=['Application Category']
// ordr[pn]=[0]
//  uid[pn]=['APP1']
// cond[pn]=['Javascript Conditional Statement']
// deps[pn]=[]
// excl[pn]=[]
// pn++

//---------------------------------------------------------------------------------------------
// Your programs here ...
//---------------------------------------------------------------------------------------------
pn=1;
prog[pn]=['.Net Framework 1.1']
uid[pn]=['DOTNETFW']
desc[pn]=['Installs Microsoft .NET Framework Redistributable Package 1.1. <i>Recommended</i>']
ordr[pn]=[1]
cmd1[pn]=['%cdrom%\\Install\\DotNetFramework\\DotNetFramework1.1.exe']
cmd2[pn]=['%cdrom%\\Install\\DotNetFramework\\DotNetFramework1.1sp1.exe /I /Q']
dflt[pn]=['yes']
cond[pn]=['FileExists("%cdrom%\\Install\\DotNetFramework\\DotNetFramework1.1.exe")']
cat[pn]=['System Tools']
pn++
//---------------------------------------------------------------------------------------------
// End of program definitions ...
//---------------------------------------------------------------------------------------------