Hey Alex, Fred here in Canada
I sympathize with you, it took me a few frustrating days to get everything working on my Pi2 Setup.
What helped was hooking up a Monitor to the Pi during Boot-up JUST to make sure all is working/booting up correctly.
As for the hard drive, I had a somewhat similar problem initially, that my system could NOT see the attached 2.5 hard drive.
In addition to not seeing it, the drive “clicked” periodically.
I resolved this by adding the following line to the /boot/config.txt found in the root of the SD Card.
From what I read, this changes the current from .6 to 1A or something like that, giving the drive the necessary extra boost of power so the Drive and Files could now be seen.
Not sure IF this will resolve your problem, as you have mentioned you introduce a powered hub, which should have corrected the problem, but its worth a try.
I’ve fiddle with a few other programs before settling into Max2play.
I find it the most encompassing Pi Application out there, so it really is worth getting it working.
Good Luck, Fred