so, about the tools let's come back on topic, actually rfactor stuff doesn't work on 64bit systems, but the game do it, will they release a compatible version with 64bit, i.e. a 32bit application that run in a 64bit pc... or 64bit users can't use their pc for modding (which will sucks big times) ??
Unless I've got the wrong end of the stick, I'm pretty sure the tools are compatible with 32-bit versions of 3dsMax - which, like most high-level software, can be run fine on 64-bit systems. So the only ones missing out are those stuck with 64-bit versions of 3dsMax.
Fortunately, 3DSMax usually comes with both 32bit and 64bit installs. So, if you don't have the 32bit installation, you can still install it fairly easily.
There may be some similarities however many of the mods aren't available from rFactorcentral, and only mods with exceptional physics will be allowed. Its not intended to compete with rFactorcentral as there are features coming that no one else has and would appear that many people want.