This release simplifies seeding for basic users, enables audio previews for files indexed by archive.org, and let’s advanced users change the location of FrostWire configuration files (enabling them to run FrostWire completely from external drives), it also fixes some search related issues and bugs.
Full Changelog in geek speak
frostwire (5.6.3) stable; urgency=high
* New Feature: Preview audio search results from Archive.org.
* New Feature: Decide wether or not to seed handpicked files
of torrents (aka Partial Downloads).
* New Hacker Feature: Change the location of FrostWire’s settings folder.
Great if you want to install FrostWire on a removable disk and
you want to maintain settings and download states.
* Fixes bug where the internet search box would be disabled after
sending file to friend.
* Updated shutdown screen lets users know about Android app when they
might be headed outside.
— FrostWire Team Sun, 04 Aug 2013 12:14:13 -0500
Official FrostWire Blog 
I had earlier versions that worked properly and never had a problem. I upgraded to the new version and now it says FrostWire is not compatible. Can you please explain this to me ? Thanks.