I said this once before but I was wrong. Ever since a Prevx release many months ago I have had problems with my screen. Easiest test is to play solitaire. Intermittently, if you drag a card, it leaves a smeared trail for the entire path. It does not go away until you minimize it to the bar and bring it back up on the screen. A few days ago Prevx updated itself with the current beta. I know when it happened because the install failed and I noticed Prevx was not running. I forced an update. From that time until now I have played lots and lots of solitaire and the problem is essentially gone. There is still some sort of very brief glitch having to do with either the mouse clicks or a screen display issue. It just has a little delay (1 second or less). Once I did get an odd problem. I tried to move a card onto a stack and it kept refusing to do it. When I clicked on the stack I was trying to move the card to, the display changed and showed there was a previously invisible card already on the stack. I have also been seeing a serious delay between the keyboard and the display when typing into a browser (like what I am doing now). That seems better, but it has not gone away. It is like something is looking at what I type, but takes too long. When it started happening I ran all sorts of scans to see if there wasa key logger. Nothing found.
We're still working on a few areas around this which we'll hopefully be able to fix in the next release. I'd keep an eye out for a .68 or newer beta version within the next couple days as I suspect this should clear up the rest of your issues
Good news. On the other hand - After 4 days of it not happening, I rebooted this morning and it is back the same as always. I am not aware of any updates being loaded, but sometimes security stuff does that. Odd. I have been having a terrible time trying to pin it on an interaction.