The smog technician is correct. Your Ford Focus needs to learn adaptation
values for the new engine as well as set the proper and required emission
monitors. In order to do this you do in fact have to drive your Ford Focus
for at least one week OR... The other option is to find a smog check repair
station who can perform the necessary driving steps on a dynamometer in
order to set the proper monitors. The Ford Dealership can definitely perform
this procedure, or you have the option of calling around various smog repair
shops to see if one has the capability of doing this as well.
We should mention also that before going through mechanic shop to set the
emission monitors you may want to go back to the DMV and explain your smog
check problem and ask for a 30 days temporary driving permit. It is not
uncommon for the DMV to issue temporary permits in situations such as yours.