Is the Script Extension folder list value be found in some config file that I can change outside TC?

I want to config the Script Extension folder value of TC automatically by my scripts which takes in svn projects url and output the script extention folder of that project on the net drive. ( As there is config file in that project which record the dir tree)

Is there possibility to do so, or has to config it manually everytime on the Option->Engine->Script Extensions?

Another question is there svn plugin that can use "svn export" instead of "svn checkout" to export some files to the dir which can avoid conflict problems? I think the fundamental function of TC can just use checkout and checkin.