This message appears if we cannot load nanoCAD and usually, it's when some other program puts dll with the same name as nanoCAD libraries, not to the Program Files folder, but to the Windows/system32 folder. It will be easy to fix the problem when we find this file - nanoCAD has a special section in the ncad.ini file to load the correct library. Usually, problems are with some geo or GIS software placing geodata.dll in the system32 folder.
It's quite easy to find problems using Dependency Walker software from http://www.dependencywalker.com/ - start depends.exe load ncad.dll and send us errors (or screenshot).
Also, if you send us what software is installed on your PC - we'll try to prepare the ncad.ini file for you.
For setup log files - the location can be different, try to type %temp% in Explorer and you should see this folder, the File name will start from nanoCAD 5.0, but the time and date should be the time of your installation.