I uploaded the GSL installer on my modeling forum for anyone interested in using GSL to make BZII models from scratch. GSL, can export X, COB, and SCN models that are convertible to XSI using 3D Exploration. The link is Gamespace Lite demo installer.
I have tutorials posted on how to prep GSL models for use with BZII. There are some limitations with the demo version of Gamespace, but the modeling software itself is pretty easy to learn compared to other similar modeling software.
BTW, a free full version Truespace 7.61 Beta 8 is also available as well. This version is actually 2 softwares package together. The 7.61 version is of limimited use to BZII model makers, but the Truespace 6.6 version is perfect as a BZII compatible model creation tool. You'll be able to create both static and animated models and props with this older TS version. Slaor and I both have used Truespace with quite a lot of success. Visit the modeliing forum for more information.