I'm using the official build of Blender 2.62 and LR 0.9 (dev) (LuxRender_CVS_20120204_32bit_SSE2_NoOpenCL) in Vista. The Pylux provided with LR.
When I try to render I get the error: "LuxRender not found at path: C/tmp/luxrender.exe". Problem is my "Luxrender Engine Configuration" panel is missing, so I can't setup the path to LR. Strange enough the preview window renders correctly the material and more annoying, in a continuous manner (I can see in the console a log entry for each iteration), making the Blender interface to flicker and taking up the CPU resources.
This is a new install and I am pretty sure at the first run I saw the LR Engine config panel, and did a setup for the path. All was ok, until the first Blender restart.
Is this a bug (is a dev version, anyways) or am I missing something?