Marlin upload problem for delta printer - help please

Hi,
I am helping someone with a (clay) Delta Type printer build as per Jonathan Keep's instructions. We have had a problem uploading the Marlin firmware and a message 'sdFile has not been declared' has been noted. I have searched for other posts on forums and can't find anything relating to this. Any tips/ideas gratefully received. Thanks, Paul.

I downloaded older version of arduino 0023 and managed to get Marlin uploaded onto controller but I am not getting any script on LCD.
I then tried changing the configuration on configuration h. file on the Marlin sketch as per Johan Rochall/Jonathan Keep and a number of posts online of people using delta printers. It doesn't seem to be working. The message I have as follows:
Highlighted line in blink.cpp -
"extern int extruder_multiply[EXTRUDERS]; // sets extrude multiply factor (in percent) for each extruder individually"
message -
Marlin.h:210: error: 'EXTRUDERS' was not declared in this scope
Marlin.h:211: error: 'EXTRUDERS' was not declared in this scope

Help please?!! Thanks, Paul.