Tomfifa

the first time me and my girlfriend at the time went to Singapore, we did have some hassle at NAIA immigration, they sent her to secondary screening, she had to fill out another form, and was interviewed. She had to ask questions as to how much money she had on her, where she was staying, and questions about myself. We barely made the boarding for our flight. I would suggest getting there early just in case, also gave her copies of the airline and hotel reservations, plus some cash to show that she had adaquate support for her projected stay. The second time we traveled, to Thailand this time, there was not problems.
We're planning another trip to Singapore in a couple of weeks, this time we're bringing her mother along...this should be fun.

Off load usually happens when the immigration officers suspect the intending traveller going to Singapore doesnt really want to go there for tourist purposes BUT to seek job instead. In your case, since she will be travelling with you (a US Citizen am i right?), there is a lower chance of her getting off load.My sister was off loaded when she first planned to visit SG. She was all alone then. So they suspected her that she will just find a job there.
Like what apple said, you dont need a CFO sticker in going there.

She doesn't need the CFO stamp to go to Singapore, even if she's traveling with you.