Hello, as the next update is getting all that closer and It will include some new levels and fixes, Project Z is now available to purchase for an Alpha price of $0.61 until the release stage. If you already have the game before the charge, don't worry you will not be charged but you may not receive any further updates after the next update.
The money is just basically a donation to help the team fund better equipment, staff and to buy new and better software to develop games on.
Here is the link:
Indievania.com