Well, it seems that things will be ok if I keep it above 60 during the day, and at or maybe one degree below thru the nights. I also have a cool mist humidifier in effective range for them as well. An update, the other buds on the other two spikes and branches are now opening. Maybe all I had to do was whine about it.
If I understood you correctly, you recently bought this with 5 spikes. Sounds terrific.
I supposed that this plant is getting used to you. It was in a facility that probably is not at all like your window sill (think commercial greenhouse). Just be patient, it will get to know you as you get to know it. When happy, it will bloom on every new growth, which is about every 9 to 12 months; sometimes sooner.