Been a Getamap user for 3 years. I love maps and planning etc and I think its well worth the money. Lots of people post routes / suggestions on here and I am straight on GetaMap to have a look.
You cannot store the maps on your mac other than printing them to pdf/jpeg as such – which I do a lot and them mark them up with a programme like SketchBook Express to use as a paper backup. You can save the images onto your phone too via email/iBook/etc.
I have added feedback on the Beta that I want the ability to export to GPX. the Beta is much better than the Silverlight bollix of the prior version (I use on Mac and PC)
I think the Beta is only available to GetaMap subscribers
I will email you some files as a sample