Sorry, I have not yet made the time to install via the script on a fresh card. Family-life keeps interfering with my personal-life, if you know what I mean.
I have 3.6 already downloaded though, so any day now.
Some more questions: Are you running the retropie-setup script via Putty while ES is running? That will probably not work nicely.
Which version of RetroPie are you using?
When I Google your error messages, it looks like the c compiler itself cannot be found. How are you calling make?