You should never use red 'heat lamps' for night time temp maintenance. You should use a ceramic heater if you 'need' heat.
Temps in the low 60s for an adults is FIIIINNNE and even mid to upper 50's is fine.... AS LONG as you get him warmed up well in the morning. Veileds can take some prety low temps, doesn't mean you should subject them to 40* weather every night.... but if you had to let it go that low he would probebly do 'OK'.
as for the egg laying bin.... sand and peet moss work great. you want more peetmost than sand... 60/40% mix.