Not sure where DS is failing. Lets try to elaborate the steps.
1. DS Console launch PXE configuration and create a WinPE PXE or you could use WinPE Managed.
2. Boot a client that is PXE enabled. do you see a PXE menu? select Boot Next this will tell us PXE is running.
3. the client gets dagent install. this is the client that tells the computer what to do.
4. DS console create a script task that will boot WinPE MAnaged or the one you created. Task should contain a simple dir.
5. Assign the task/job to the client. the client reboots into Winpe and the dagent in winpe comes up and checks with the deployment server for any jobs. if there is a job/task it will do it. Once it is done it will reboot to production (OS).
sorry for assuming to much just want to see where in the process DS is failing.
Nelo