I do the same as mazin does, I drop the exe (which I rename to foxit.exe) into a directory and then run an AutoIt script to handle all the dirty work. The bulk of it is registry changes, here is the script:
CODE
RegWrite("HKCR\.pdf","","REG_SZ","FoxitReader.Document")
RegWrite("HKCR\.pdf","Content Type","REG_SZ","application/pdf")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}","","REG_SZ","PDF Document")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\AuxUserType\2")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\AuxUserType\3","","REG_SZ","Foxit Reader")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\DefaultExtension","","REG_SZ",".pdf, PDF Files(*.pdf)")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\DefaultIcon","","REG_SZ",$AFI_BASE&"\usr\"&$AFI_XXX&"\Foxit.exe,1")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\InprocHandler32","","REG_SZ","ole32.dll")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\LocalServer32")
RegWrite("HKCR\CLSID\{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}\ProgID","","REG_SZ","FoxitReader.Document")
RegWrite("HKCR\FoxitReader.Document","","REG_SZ","PDF Document")
RegWrite("HKCR\FoxitReader.Document","BrowseInPlace","REG_SZ",1)
RegWrite("HKCR\FoxitReader.Document\CLSID")
RegWrite("HKCR\FoxitReader.Document\DefaultIcon","","REG_SZ",$AFI_BASE&"\usr\"&$AFI_XXX&"\Foxit.exe,1")
RegWrite("HKCR\FoxitReader.Document\protocol\StdFileEditing\server")
RegWrite("HKCR\FoxitReader.Document\protocol\StdFileEditing\server")
RegWrite("HKCR\FoxitReader.Document\shell\open\command","","REG_SZ",'"'&$AFI_BASE&'\usr\'&$AFI_XXX&'\Foxit.exe" "%1"')
RegWrite("HKCR\MIME\Database\Content Type\application/pdf","CLSID","REG_SZ","{14E8BBD8-1D1C-4D56-A4DA-D20B75EB814E}")
RegWrite("HKCR\MIME\Database\Content Type\application/pdf","Extension","REG_SZ",".pdf")
RegWrite("HKU\.Default\Software\Foxit Software\Foxit Reader\MainFrame","ShowEditorAd_908","REG_SZ",0)
RegWrite("HKU\.Default\Software\Foxit Software\Foxit Reader\MainFrame","ShowReaderAd_908","REG_SZ",0)
RegWrite("HKU\.Default\Software\Foxit Software\Foxit Reader\MainFrame","ShowTypewriterAd_908","REG_SZ",0)
RegWrite("HKU\.Default\Software\Foxit Software\Foxit Reader\MainFrame","ShowPOAd_908","REG_SZ",0)
RegWrite("HKU\.Default\Software\Foxit Software\Foxit Reader\MainFrame","ShowSDKAd_908","REG_SZ",0)
RegWrite("HKCU\Software\Foxit Software\Foxit Reader\MainFrame","ShowEditorAd_908","REG_SZ",0)
RegWrite("HKCU\Software\Foxit Software\Foxit Reader\MainFrame","ShowReaderAd_908","REG_SZ",0)
RegWrite("HKCU\Software\Foxit Software\Foxit Reader\MainFrame","ShowTypewriterAd_908","REG_SZ",0)
RegWrite("HKCU\Software\Foxit Software\Foxit Reader\MainFrame","ShowPOAd_908","REG_SZ",0)
RegWrite("HKCU\Software\Foxit Software\Foxit Reader\MainFrame","ShowSDKAd_908","REG_SZ",0)
You can't just use this one since I have my custom network paths, but you should be able to hack it.
Oh, and there are some extra settings in there that disable the little pink ad bar. Since it's not changing anything I think it would be okay, but if a mod doesn't think it's cool I'll change it if they want me to.
And yes, there are duplicates in there...some apply to the current user, and others to the default user profile. I do this because I don't run these installs during the unattended, but under a 'special' user I make for these tasks. Because of that the 'special' users profile is already created so it won't pull the reg settings from the default profile.
Good luck!