AnD4D
Yes, I have made a Time Manager plugin, which has different types of counters.
You can find the plugin here: http://www.scirra.com/forum/topic49030.html
The plugin counter works basically the same way as the manual timer, but its much easier and faster to create and use, than doing it the manual way. And you have a lot of different features you can do with the plugin, which you have to create yourself with the manual method.
The downside with a plugin, is that it's not accepted to use 3rd party plugins in the Scirra Arcade. So if you want to publish your game there, you have to go the manual way.