If you have and know how to use shop tools, try a table saw to cut solid rail like Atlas 3 rail. Keep the blade low and go slow. Nickle silver is soft so the blade will stay sharp for lots of cuts. I place a piece of blue tape at the edge I want to cut. Try a couple test cuts to see how it goes. Be careful because fingers don't grow back.
Dremel works well for cutting track that has been placed and secured. It still takes a little practice. I always test stuff before I commit it to places that are permanent.
Just my $00.02
DL