Version 0.5 is out! Get it from https://launchpad.net/lierolibre/+download.
I've been working on a project known as lierolibre for a while now, you can get hold of the latest version from:https://launchpad.net/lierolibre, there are also packages available for Ubuntu 11.10 and 12.04 in a PPA.
lierolibre is a direct fork from Liero (formerly OpenLiero), which itself was a remake of LIERO.
Give it a try, report a bug or two, comments welcome!
The main changes done in lierolibre compared to Liero is:
1. Relicensing and replacement of non-free content:
The original LIERO was released under a non-free "freeware" license, have spoken to the original developer which has kindly agreed to relicense all content which was created by him under the WTFPL. Graphics and game variables are what ends up being used in lierolibre out of this content.
The sounds in LIERO/Liero, which came from Molez, which itself had borrowed some of them from proprietary games, have all been replaced with original sounds (WTFPL) created by "sea".
lierolibre can in addition to reading from LIERO.EXE read and write game vars to a plaintext file instead, and this is what comes shipped by default.
2. General adaptation to *nix
Added in lierolibre is a simple module to allow for $HOME and system content separation. For ease of installation there's autotools (though freetype jam still works for the compilation step).
3. Scripts to handle the game data
Finally, lierolibre also includes a bunch of scripts to handle the extraction and repacking of sound, graphics and levels for Liero. In order to make modification of these more accessible. It is still quite limited, for example the graphics uses raw 8bit pixel values, which are extracted to greyscale xpm files, although the palette used in the game itself differs, so if one wanted to do serious editing one would need to keep referencing the liero palette (available in liero.cfg). It is a resonable compromise for now though, and somewhat nicer than using a hex editor, as it were.
If you happen to create some content for lierolibre, or find something which has a free license and might fit, leave a comment, or report a feature request bug
There's also quite a lot of changes behind the scenes, if you want the gory details, have a look in the git log, (gitorious repository is linked from Launchpad).