Page numbering and format can be defined per section so you can get to the required format by creating two sections in your document and setting the page numbering accordingly

- Start with an empty document
- "Insert - Auto Page Number", select the "Section" option for "Show In" and set the format to roman numbers. This is now your TOC section.
- Use "Insert - Section break" to create a new section
- "Insert - Auto Page Number" again, select the "Section" option for "Show In" and set the format to arabic numbers
- With the cursor in the second section, open the inspector 

     ![enter image description here][1]

    and reset the page number to 1


  [1]: https://i.sstatic.net/iBg0Y.jpg