Yes.  The STOP button does just that (Widget or Home screen).  It stops logging GPS entries into your database and saves battery.   BEWARE!  you are not logging your location when in STOP mode.  Remember to go to RIDER/NORIDER/PERSONAL when you need to start tracking again.

Expenses Yes!  You can enter backdated expenses directly into MyRideTrac on the EXPENSES screen.  Just dial in the odometer number you want, key in the date and select the expense type from the spinner wheel. Miles Yes - in the spreadsheet but not directly into MyRideTrac on your phone - yet.  Miles are tracked automatically by the GPS system built into your phone.  The easiest way to add miles to your log is to use the handy spreadsheet that is sent with your SEND REPORT email.  You can add a summary of miles to the top or bottom of the spreadsheet very easily using Google Docs or Excel.  Send an email to Support if you want some help.

This is caused when the app is killed before an event is ended either by switching to another event (RIDER/NORIDER/PERSONAL/STOP.  MyRideTrac can run all the time in the background.  There should be no need to "kill" the app by swiping up.  Nothing bad happens if you do, you just may not get an end date entered into your log.