The sourcecode of sensobots is well commented, so I guess it is the best place to start reading. Manuals for the client and the servers are below, together with a little tutorial to setup irrlicht and Eclipse/CDT on a linux system.

Manuals

Sensobots compilation manual

Sensobots client manual

Sensobots server manual

Tutorials

Tutorial on setting up Irrlicht in Eclipse/CDT under Linux

Known Bugs and Issues

The sensobots "Known Bugs" list