Cannot sort 2 long columns

I can sort 2 columns that are short. One column is the date, and second column is my weight. I am sorting from high to low.
The enclosed attachment is a Steps Recorder file showing the errors that happen when I sort a whole long spreadsheet.
Calc v Windows 8.1 English

Forget the attachment; it will not upload. link text

I figured it out finally, after many tries. I need to copy the columns I want to sort and paste them in a new spreadsheet with Paste Special. I deselected formula, and got just numbers. After the sort, both columns sorted. Then, I formatted the date column to be Date rather than number.