Keyla needs restart after screen locking in Windows 8 about keyla HOT 5 OPEN

Having read the sources, I can say that they should handle the 
WM_WTSESSION_CHANGE message: 
http://msdn.microsoft.com/en-us/library/windows/desktop/aa383828%28v=vs.85%29.as
px

Unfortunately, I can't produce a working patch right now.

Thanks for filing this bug report.  Judging from the behaviour, seems that 
Windows no longer calls keyla after locking and unlocking the screen.  If you 
indeed want to hack the code, you may try to remove and attach again the 
keyla's hook after you receive the message that the screen has been unlocked.  
By the way, are you sure the message we need is WM_WTSESSION_CHANGE?  In the 
MSDN article you linked it's under Remote Services API that does not seem 
related to me.

I also observe a behavior where the switching no longer works - on Windows 7.

It does apparently happen consistently on Win+L, but also often happen when the 
"screensaver" lock screen kicks in - but evidently not always..

It is EXTREMELY annoying. Is it easy to fix? I have been thinking of 
auto-killing it every minute or so, and just restarting it..!

Any chance of fixing this RSN? Would US$50 be an incentive?  (Windows 7)

Maybe it's common bug with #27, see for patched version in comments.