Question 1: SVG is a type of file. It uses XML to let the computer change text into images.
Question 2: In order to tell wheather a row represents a road, you can look at fullname and roadflg. If you were to try to locate a particular address, you would need ROADFLG, FULLNAME, ZIPL, ZIPR RTOADD, and RFROMADD.
Question 3: I would go into properties and set the rule ZIPL="14261".