There seems to be some issues with the ice maker GUI.

• Clicking on the arrow shows food processor recipes (NEI)
• Clicking next to the input slot (and in fact also slightly inside the input slot) on the right side shows either ice maker recipes or evaporator recipes. If you hit that area when trying to place an item into the input slot it will fall on the ground.

Thank you!
These will be fix in 2.6d.
And, another machine (processor and evaporator) will support NEI recipe button.