fused glass and silver clay

1) Can Silver clay be combined with fused glass? What would be the general technique? Do you fire the glass, and then add the clay and re-fire?
I have done both. If you use the ACS 650 series, it fires at 1200°F for 1/2 hr. At this temperature, the glass only slumps a little so I do my slumping first and then build up the Art Clay on the glass. There is also an Art Clay product called 650 Overlay Paste. This is a great material for working with glass, glazed ceramic or porcelain. Over all, you need to do some experiments and find the best way to work these materials together
2) I'm not sure if this can be answered here or not... I am trying to fuse S/S wire within glass -90 COE and dichroic-. I made one piece, it looked OK, but it had a couple of bubbles - which I think is just a matter of practice (this was the first time I fired anything) as well as the silver looking "rusty" or tarnished. What can I do to avoid /prep the silver with, etc.?
Fusing silver in sometimes works and sometimes not - the 'bubbles' you mentioned may be the beginning of small cracks caused by incompatibility problems. The 'rusty or tarnished ' effect will happen when heating glass and silver together. It is usually a yellow to dark yellow brown and is called silver stain - it is part of the reaction between the glass and the silver. This can also be a further concern as you work with the Art Clay, dichro and glass.
Again - experiments are a great teacher.
If you go to the top of the page in the forum and use the search window, put in +glass +fusing [the pluses are important] This will show you a number of discussions about glass.