While we don't mind helping you, this does not appear to be NITdroid specific. It seems to be a common Android error:

* http://forum.xda-developers.com/show....php?t=1113688

* http://www.droidforums.net/forum/dro...partition.html

* http://www.chainfire.eu/projects/44/Chainfire3D/

Googling hasn't resulted in a solution but...

My guess is the error is not actually related to free space, that was simply the script's "best guess".

* http://www.chainfire.eu/articles/97/...v1_0_released/

Looks like some sort of hard-coded permission issue. One of the commenters alludes to being able to change the install directory in the "Pro"/paid version of chainfire3d.

However it is also possible that this simply won't work in NITdroid since this utility seems to be a low-layer man-in-middle for opengl and I'm not aware of the state of opengl support in NITdroid. This is just speculation though, unlikely that the error is in anyway related to this, more of a possible error to crop up once you actually try to use the "driver", your current error is simply the installer.