Been having this issue as well. Very annoying.
try holding down the alt key and clicking at the same time. it seems to have resolved the issue for me.
I have the same issue when loggin into Win7 32 or 64 using chrome. Very annoying.
Same issue, worked on my XP and Vista machines, doesn't work with Windows 7. Have to select and hit <enter> or right-click and "open".
Same problem. I use LogMeIn Free, my host is Windows 7 Ent 32bit, and the client is Firefox 11.0 with current version Flash, on Windows 7 Ent 64bit.