there is some information in here to edit a msi file for FC.
http://docs.fortinet.com/fclient/forticlient-endpoint-security-administration.pdf
I use the following .bat file for my msi install. that way I do not have to worry about minor internal changes to the msi that would cause issue with a .mst file.
msiexec /i FortiClient.msi USESWUID=1 LICENSE=xxxxxxxxxxxxxxxxxxxxxxxxxxxx LICENSE_VALIDATION_TYPE=1 FMGRENABLED=1 FMGRIP=xxxxxxx.xxxxxx.com FMGRTRUSTEDIPS=xxxxx.xxxxx.com NOREMEMBER_VPN_PWD=1 /qb /L*v c:\fcinstall.log
Hope this was helpful
firewalls firewalls everywhere