Found this thread through the search function.
I am having pretty much the same issue with the game not registering double clicks unless the clicks are a millisecond after one another. Tried updating my G9 mouse drivers, rebooting the PC, running ArmA 2 with no mods or anything else loaded with patch 1.04 or the new beta patch. I can't remember the long string of numbers which version that was.
I am currently running Windows XP Home Edition and my hardware is as follows:
CPU: AMD Phenom II X4 955, 3.2GHz
Motherboard: Asus M4A785TD-V EVO, AM3, 785G
Memory: 4 GB (2x2GB) DDR3 PC3-12800, 1600MHz
Graphics Card: HIS HD 4890 Turbo 1GB
And as stated already I am using a Logitech G9 laser mouse with the latest setpoint drivers.
If anymore information is needed just ask.
Thank you.