Nebulae v2 layering multiple usb sample files in record mode?

Hi! I was just wondering if there is any way to layer parts of different multiple wav files from the usb stick on top of eachother in record mode. I know you can record live audio then blend that with new layers of live audio with the blend knob (in live mode, with source light illuminated) and I know you can also “overdub” bits of samples from the usb stick on top of the live recorded buffer, but I haven’t been able to just “blend in” bits of samples from the usb stick, it either replaces that chunk with new audio or I’m stuck with original buffer. It would be great to have a few samples lined up on the usb stick, start with one sample, then slowly mix in the second, etc. without having to keep feeding it live audio. Any help is greatly appreciated thanks!