If I recall, the recording level is pre-master, which means whatever the channel levels are set to is basically where that recording level goes, minus the headroom. If you aim for around the 0dB mark, you should be okay. Worst case scenario, if you record your set and find it's low, just pop it into an audio editor (like Audacity, which is free), and up the volume. Better to be low than high and have things clipped and distorted!
As for the recording-elapsed, I don't believe there is a feature for that, but I'll suggest it to the engineers.