Ka,
Noticed we haven't answered your question about Se toning..my advice, and I think the general advice here is ALWAYS tone, either with Selenium or one of the sulfide toners for permance. The sulfides with give brown or sepia color. Follow Tim Rudmans advice on selenium if you do not want a color change, I think a 1+9 dilution for 5 to 10 minutes will do..compare to an untoned print, you will see a change. Search the forums for additonal information as others here can answer better than I.

Good Luck.