This is BETA1 of ACL for Drupal 7, ported from 6.x-1.1.
We do not recommend installing it on a production site, but we encourage you to test it and provide feedback (both good and bad!) in the issues queue. Seefor details.
Note: The devel_node_access (DNA) module, which is part of the Devel module, provides an in-depth view into the inner workings of node access, especially if you enable its debug mode at admin/config/development/devel#edit-devel-node-access-debug-mode and its second block. This is a big help for understanding the forces that control access to any given node.