Link works for me.  http://www.koshyjohn.com/software/memclean/ As for vetting.  As i say it works for me ... View more

When I work in LR4 (Original) RC1 or 2 I found that the use of memory just kept accumulating, the prog became less responsive and showed signs of a gradual slowdown. I found the only way to reduce it was to close LR4 and restart then the responsiveness was good, memory use low and it worked.  After further editing memory use increased prog became sluggish, close down and restart.  With this memory prog running I can keep working normally without the need to keep restarting the prog mis edit.  ... View more

I have recently downloaded free software called memory cleaner.  If you set the options to auto clear processes and system cache every 5 mins it reworks the amount of memory LR4 RC2 (and all other processes) is accumulating.  It works on my machine.  Liink is http://www.koshyjohn.com/software/memclean/ ... View more

I currently have an open service ticket on many of the points you mention and they are now referring this upward to the technical section.  I think they are very aware of the problems but not enough people are registering their problems through the adobe siite. As previous contributors have said.  Register the problems with Adobe however minor they may seem.  Enough people registering the same problems will get action taken. ... View more

Not sure if this is the place to raise this one but when sychronising in the develop module only the exposure setting for say 100 images only the first 6-12 are changed.  When synchronising CHECK ALL is used then the exposure is changed on all the images? ... View more

Now confirmed you can load old catalogs in LR4 after virgin start up and they do convert but run sluggish which is what adobe have identified and presumably are working a fix.  When you revert to the virgin catalog in LR4 and work on new imports via LR4 the software performs to LR3 speeds. ... View more

You dont delete yuor catalogs as they are saved in a different folder ... View more

I have had a call back from Adobe support and there would seem to be issues with settings imported from beta and previous versions.  There advice and it worked for me to to remove the LR4 beta version with windows software then reboot your machine.  Then in windows 7 go to c:users/pc/appdata/roaming/adobe and then drag the lightroom folder to the desktop.  Then start LR4 and create a new catalog.  DO NOT IMPORT OLD ONE.  This will create a virgin set up.  LR4 on my machine now performs as well as LR3 did.  Have not yet loaded a old catalog from LR3 so hoping that will be OK ... View more