Hmm, maybe I am being a little paranoid. still, one leaf is a lot when you only had 10 to start with.

LOL... I get it, but trust me. Shock happens, and it tends to make plants lose leaves. Getting it into a The right cultural environment/home greatly increases your success long term. I had a few that lost almost all of their leaves until I got it in a more appropriate home/setting. They are thriving to this day. Just keep an eye on it and the roots. Modify if need be, but one leaf shouldn't worry you.

Ray has a website with good info. If you haven't seen it yet you should check it out. He has a section on cooling orchids that might help
"Stretch" Your Growing Conditions

I am getting some major orchid lag. After keeping them on my bench for two weeks thinking they were happy I finally get them into the climate controlled tank THEN they start to lose leaves and droop at the tips. I was so busy researching that I forgot the basics: Plants are just like people, they just take longer to complain.

Hopefully now they are in a better environment they will pick up a bit.