MPC Essentials + MPK MIni

Hi all, just a quick question regarding the MPC Essentials software that comes with the MPK Mini. Is it possible to multi track, say lay down a beat with the pads and a few samples then record synth over the beat using the keys? I presumed this would be a given for any piece of music software but I am having problems. I record a beat then switch to plugin to record synth and the beat is gone? Also there is no option to record a new track over the current one. Am I simply being silly or is this a genuine restriction?

All help appreciated, Thanks.