I just gave it a spin on my office system: Windows 7 x64 with Google Sketchup 7.16860 (free version).
I first removed the old plugin, made sure all files were removed from the plugins folder that i added with the last plugin,
then extracted the contents of this version in the plugins dir, and opened the sports hall model again. (the same one i mailed you)
As you can see, it's not all %100 yet
There are various textures that don't make it into octane, and also there's some geometry missing in the blue front window,
aswell as the fact that the corrugated iron material (which you can see in the screenshot of the node inspector, and the black arrow points to it),
is a glossy material with a very low roughness, making it almost a perfect specular mirror.
I think you should make defaults for the glossy material much more rough, like 0.005.
I'm still getting the error when i launch the plugin, i just hit ignore and continue.
(i've got the default IE installed on my system, never upgraded it as i don't use it, i use google chrome, of which a very recent version is installed)
Hope you can fix this, nevertheless good work