I have called PayPal today. They are sending me an email to send to anyone who purchases from me on itch.io. This email will have instructions for you the buyer to allow PayPal to release the funds and that will give you access to what you've purchased.
The 4 payments that were "on hold" have no been released. I have stressed that although I agree that there is a need to build trust as a seller with PayPal what they're doing is causing mistrust between me and my customers.
This may keep occuring until I reach the 10No. transactions and £200.00 selling thereshold. If this is the case I will call PayPal once per week to have funds released until this is no longer a problem.
Again, I'm sincerly sorry you have to deal with this hassel.
Regards,
Snowy.