Multiplicity Issues when playing games WoW

Hello, i was trying to 2 box using Multiplicity, it seems to work really well but everynow and then i will lose the ability to click into things on both computers. i can still move the mouse around,  i still have functionality of the keyboard, but for some odd reason i cant left click anything. it even shows the graphic of it clicking like the button depression. but i get no action. a restart of both comps fixs the issue.

A little background, I started using the free trial yestuday, i really like the program so far, and im really thinking about purchasing it but with this odd bug im not sure if ill want to. Is it just a bug with the free trial software?

Primary comp = 3.0 core2duo 4gb ram 500gb hd, 2 dvd drives, g15 gaming keyboard,  mouse is Logitech G5 7 button mouse. 4870 1gb hd monitor is a  24inch hp

Secondary comp =  vid 8800 geforce gts 512mb, 2.13 core2duo, 4gb ram,  250 gb hd, monitor is a 19inch LG

Any help on this or information regarding something similar would be awesome!