Sounds like your date field is not big enough for fmgo 13. FileMaker 13 can add a lot of padding to the beginning and ending of a field which can result in a field being to small on the layout.
The screens were developed with FileMaker 12.
The screens might have been developed in 12 but you are now trying to open it in 13. Still recommend making the field bigger to see if that solves your problem. If yes, then you have two choices. Leave the field bigger or open the file in FileMaker 13 and reformat the field to accommodate the smaller size that you want.
Note that in FM GO 13, you can use the Inspector to remove or change the padding specified by the current theme for a given field.