Being in the office, I don't have all the exact version numbers available at the moment. I have XP Pro with SP 1 installed, recently downloaded and installed all available patches with WindowsUpdate. The ET has the update installed as well.
After having jumped onto that box, I stand similar to your Error3 image, but more to the left, quite in the corner. There I do a single Machete slash by hitting the left mouse button and the cut scene starts immediately.
The problem might be related to the position where you stand, I don't know. As I said, it worked for me several times.