1. cycling normally take about a month with many factors involved. a reliable testkit will tell u when ur cycling is over. get ammonia, nitrite, nitrate.
2.i guess the ammonia might have killed the hermit.
3. no experience but i doubt so.
4.depending on ur tank size, a nano 6025 , or a seio 620 might be good.
talk to more reefers .
5.at least biweekly to prevent nitrate buildup
6.normally they will find food for themselves. but no harm feeding them pellets.
7.as long as ur temperature is not way too high. u might wanna consider fan.
8.as the tank is small, u might wanna try clownfishes, gobies, pygmy angels, dottyback,gramma.
9. as long as the time taken for the rock to be out of water is not too long, it is okie.
=)