Dusting is easy-peasy! You can use canned air, holding the air stream about 12 inches from the piece. Or, use a slightly damp chip brush and go over the piece. This is what I do, simply because I have a gazillion of these in the studio! You can find these brushes at any hardware or craft box store.
The application of resin to the fiber is what gives the pieces the ability to be cast into shapes (and it is really fun to do!). However, resin may soften in heat in excess of 180 degrees. There is a window piece hanging in my studio. It is in a south window with plenty of sun exposure. The piece is away from the glass to allow for air circulation.
If you have any questions, shoot me an email!
I know you'll enjoy your vessel or window panel for years to come!