It was time to re-do the pomodoro timer and make it simpler and more reliable. to that end, I decided to use a Teensy 3.2 (overkill) and a Sparkfun Serial Seven Segment display. The code is pomo_s7s_1011 and is in the dropbox project folder.
The white 3mm LEDs indicate state (5 min/25 min countdown) and with 220 ohm resistors are too bright, but this is a small defect. Otherwise the system is working very well and on a small proto board on top of an altoids tin.
There are simply 2 switches, 2 LEDs, 1 speaker out, and 1 serial out for the sparkfun serial display. The pins are 3 & 5 for the pushbuttons, 2 & 7 for the LEDs, pin 4 for the speaker output (driving directly a small microspeaker from an iPhone), and the serial port, pin 1, running at 9600 Baud. The push buttons select either: 5 or 25 minutes duration, and the other resets the timer when a time out condition exists.