While the timers technically have a pause/resume option, it does not work the way most people would expect it to work.
Example: A timer running for 60 seconds is paused at 30 seconds.
Then the timer is resumed 45 seconds later.
Most people would expect that the timer would continue for 30 seconds at that point, making it (realistically) a 105 second timer.
However, in practice (and I've seen this mentioned in the bug reports section before) the timer does not do this, and simply executes the command(s) when the timer is resumed. The actual timer keeps counting to the 60 second mark, then stops and holds the command until the timer is resumed.
Realistically you're going to have to have something that will start/stop the timer.