The USB/SWD JTAG module provided with the Eval board supports 4-wire and 2-wire connection for debugging as per documentation. I tried the following combinations for my eval board and custom hardware. My custom hardware has only DIO and CLK for programming and no external xtal.
1. Using IAR to program in 4-wire mode = pass on EVM
1. Using IAR to program in 2-wire mode = pass on EVM, fail on custom hardware
1. Using CM3WSD to program in 4-wire mode = pass
1. Using CM3WSD to program in 2-wire mode = fail
Please suggest ways to resolve 2-wire programming