I am trying a simple C project and it will not do anything on the STK300 board. Why?
The C Compiler is very device specific and having wrong device set in Project > Configuration Options means that code will not run on target. This is usually because of subroutine calls as stack pointer is set for wrong device. Watch out for M103C fuse on ATmega128. If this fuse is set, the device effectively becomes an ATmega103 and C code written for ATmega128 will not run. Clear this fuse to make code work.