http://www.incursion-roguelike.net/
https://groups.google.com/forum/#!forum/incursion
After going dark a great while ago in a rewrite of epic proportions that ended up getting bogged down and other projects pursued by the developer, things were looking grim. However, now the classic version of the game from just prior to said grand rewrite has been made available in all respects as Open Source, and OGL in all other related thematic aspects to boot(which is handy as there are some nicely flavorful things afoot), and work is well underway to reforge it into far better technical shape to actually better function outright and otherwise(The old Allegro backbone has already been killed dead, with the usurper to the throne being SDL2 and libtcod for instance):
https://bitbucket.org/rmtew/incursion-roguelike
Any and all help and fresh ticket filing is sought after as it is a long road ahead, though an optimistic one considering what all has been done in these few weeks in terms of releases.
Similar as a spiritual successor of sorts from before this recent above event, Veins of the Earth has made great strides with the T-Engine as well as availing itself of a great many aspects and ideas since the open sourcing happened:
http://www.roguebasin.com/index.php?title=The_Veins_of_the_Earth
So yeah, 2 newly enlivened OGL fellow travelers alongside the KotC stable---the only company it has really even if both dovetail moreso into the Roguelike sensibilities than the cRPG ones. Each are, needless to say, now rather very transparent about their workings and mechanisms---so that's for the benefit of any and all going forward.