I am running MixPad on Windows OS.I bought my license. I sent a file to my guitar player who is running MixPad on Mac OS. His version of MixPad can not 'read it". Is there an export function in the licensed Windows OS version, to export in Mac OS file format? He said he "was able to download MixPad, but did not mention purchasing a license. Is it possible the "trial" download for Mac OS does not have the ability to read Windows OS version files- BUT licensed Mac version would?