Ok firstly I should point out it worked for half a day after I made a PayPal Donation to get the PRO version in the morning then stopped working and asked me to make ANOTHER donation for the PRO version in the afternoon.
I am sure I am an exception rather than the rule and I have contacted them over the issue. I type this so others are aware there can be issues.

Having said that I now have it working again after being e-mailed an activation link following my complaint. I found the support to be be pretty good.
Had I not encountered the, albiet, temporary problem I would have given 5 stars.