They also have a setup.ini file. Does this help?
[Info]
Name=INTL
Version=1.00.000
DiskSpace=8000 ;DiskSpace requirement in KB
[Startup]
CmdLine=/L*v "C:\kareo.log"
SuppressWrongOS=Y
ScriptDriven=1
ScriptVer=12.0.0.49974
DotNetOptionalInstallIfSilent=N
OnUpgrade=1
RequireExactLangMatch=0404,0804
Product=Kareo
PackageName=Kareo.msi
EnableLangDlg=N
LogResults=N
UI=1000
DoMaintenance=Y
ProductCode={6A012CB9-3A26-48A4-B59A-0442C5DA7558}
ProductVersion=1.56.4094.31812
SuppressReboot=Y
Skin=setup.isn
LauncherName=kareo_setup.exe
DotNetVersion=v2.0.50727
DotNetSPRequired=
UseDotNetUI=N
DotNetCoreSetupUILang=1033
DotNetLangPacks=
DotNetFxCmd=
DotNetLangPackCmd=
DotNetOptional=N
DotNetDelayReboot=N
PackageCode={104A526F-2860-42B2-879C-65A12E964783}
Source=0
[MsiVersion]
3.1.4000.2435=SupportOSMsi30
[SupportOSMsi11] ;Supported platforms for MSI 1.1
Win95=1
Win98=1
WinNT4SP3=1
[SupportOSMsi12] ;Supported platforms for MSI 1.2
Win95=1
Win98=1
WinME=1
WinNT4SP3=1
[SupportOS] ;Supported platforms for MSI 2.0
Win95=1
Win98=1
WinME=1
WinNT4SP6=1
Win2K=1
[SupportOSMsi30] ;Supported platforms for MSI 3.0
Win2KSP3=1
WinXP=1
Win2003Server=1
[Win95]
MajorVer=4
MinorVer=0
MinorVerMax=1
BuildNo=950
PlatformId=1
[Win98]
MajorVer=4
MinorVer=10
MinorVerMax=11
BuildNo=1998
PlatformId=1
[WinME]
MajorVer=4
MinorVer=90
MinorVerMax=91
BuildNo=3000
PlatformId=1
[WinNT4SP3]
MajorVer=4
MinorVer=0
MinorVerMax=1
BuildNo=1381
PlatformId=2
ServicePack=768
[WinNT4SP6]
MajorVer=4
MinorVer=0
MinorVerMax=1
BuildNo=1381
PlatformId=2
ServicePack=1536
[Win2K]
MajorVer=5
MinorVer=0
MinorVerMax=1
BuildNo=2195
PlatformId=2
[Win2KSP3]
MajorVer=5
MinorVer=0
MinorVerMax=1
BuildNo=2195
PlatformId=2
ServicePack=768
[WinXP]
MajorVer=5
MinorVer=1
MinorVerMax=2
BuildNo=2600
PlatformId=2
[Win2003Server]
MajorVer=5
MinorVer=2
MinorVerMax=3
BuildNo=2600
PlatformId=2
[Kareo.msi]
CertKey=Kareo.isc
Type=0
Location=Kareo.msi
[Languages]
count=1
default=409
key0=409
[Setup.bmp]
0=setup.bmp
Type=1
[dotnetfx.exe]
CertKey=DotNet.isc
Type=2
Location=http://autoupdate.kareo.com/Redistribution/dotnet2/installshield/dotnetfx.exe
[WindowsInstaller-KB893803-x86.exe]
Type=1
Location=WindowsInstaller-KB893803-x86.exe
