(1 to: 64) collect: [:i| ((!Segment_ suffix2: i) rounded)]
creates an Array with the individually-numbered !Segment EventValues. If you evaluate using CtrlY, the printed result doesn't include the curly braces around each element, but the actual object returned by the code is an Array with !Segment_01 rounded, etc.
You should be able to use the Array value directly without printing it out first (where are you using this Array? Which parameter field?)