I may have a solution for you on the report name.
My load was from c:\test\<report file name>.
I believe the MAX_PATH for file names is 260 chars. Now, when the report engine loads the report, it actually makes a temp copy that has a guid attached to it. So if your path was something like
c:\test\my folder\another folder\one more folder\... the load path may have exceeded the allowed path length. To test, copy the report to something like c:\test and see if that loads. It should. Like I said, mine loaded with the name I specified in my post from July 17
- Ludek