Help! How to set PML parameters with metal?

Hi,
im using Rsoft fullwave package to calculate propagation of surface plasmon in
metal-air-metal waveguide (the same structure in the attached paper), I
want to get the transmission spectrum at the output of the waveguide, here I meet
some problems, is anyone can help me?

1. I feel very confused about the parameters setting of the boundary condition.
here I use PML with a reflection coefficient of 1e(-8) as the BC and it is
attached to the metal (Ag), but the result is terrible(see the attached picture)
, it seems a lot of light is reflected from the boundary and cause the error? I
dont know why, can PML attach to metal? How should I set the width and
reflection coefficient of the PML to get the right result? When I increase the
width to more than 1 micrometre, the software warns that the area of the PML is
larger than 70% and the result may be imprecise... My simulation file is attached below, please change back the file type from .jpg to .ind.

2. how can I get the transmission spectrum at the output of the waveguide? I
dont know how set the time monitor to get the power normalized to the incident
light, If any one is familiar with the software, please help me.

Thanks a lot!

the reflection coeffecient is 1e-8

Added after 3 minutes:

sorry, the simulation file cannot download with .jpg, I have changed it to .pdf.