I had never installed SMF before, actually not even looked at it much.
In less than 20 minutes I installed it and the following mods, with no problems.
This install can be found at
http://simple2say.com/SMF/ if you want to look it over. It is straight out of the box.
Using PHPsuExec, when it calls for chmoding files to 777 for install,
you just ignore that step. I never chmoded a file.
Chmod is only required when you have 777 folders or files when the PHP conversion is made from an Apache module.
Once your scripts are working --
and all future installs -- with phpSUexec
you will never need to chmod a file or folder again.