You've got a bunch of things for lab examination!

burnt piece - seems to have been torched with lighter fluid. Neat because you happen to have:
lighter - yup was full of lighter fluid
colored glass - a wine glass probably
rags - Ecuador or Guatemala cotton fiber with jet fuel on it
fumes - a fuel accelerant
window shard - shows the outside of the window was going away (i.e. window broken from inside)
cast - kneeprint, not too helpful except to say someone knelt outside

Use the computer on the fingerprint from the paper on the desk to see it is James Ritchie's. His rap sheet says he has done insurance fraud in the past. And he of course is who was named as a suspect! Interesting.

If you hop over to the cops, you learn that James Ritchie has his HQ downtown and you get a new location to go chat with him.

CSI Crime scene Investigation Walkthrough