Welcome adrianp

Your first problem was a bug and has been fixed in KDE SC 4.5.2 which has been sent to the PASS repo and should be in the public repositories soon. There are quite a few threads about this on the forum. If you search for it, you'll find the info.
This was the announcement on Tex's identica (also on his twitter account)
A lot of people have been having issues with icons on desktops and panels that may be dealt with in KDE SC 4.5.2 which is coming very soon. Sorry, I can't help with your other 2 issues but have you tried searching the forum?