If you use Dropbox for all your Function/Food-Order sheets, here's a guide to make the process more seamless when adding the urls to your booking.
1) Locate your file in your drop box:
2) Right Click the file and select Copy Dropbox Link:
This copies the URL needed for ResDiary.
3) Select > Edit the booking
4) Select the Function Sheet/Food Order Icon:
5) This will open the Add/View Function Sheet or Food-Order pop up window:
6) Right click in the field and select Paste:
7) Click Save. This has now added the url to this booking
8) You can then Save the booking and now access the sheet via this button:
This should open the sheet in a new window.