hello and welcome to the forum!
kde4.4 doesn't exist yet so you should edit your post(unless you are testing 2010 beta 1 and this one is not supported, it is for report errors and test it)
i am using compiz right now and all works perfectly, using it since 2007/8, using it on kde4.3 since october without problems(in fact it crash far more less than on kde3)
have you verified that your video card is properly installed(right drivers) and have you disabled kde4 desktop effects?(in kde control center)
one interferes the other, can't be enabled both
i don't have compiz kde installed, in fact it doesn't mention it when i search in synaptic that package you mention, it seems that i installed task-compiz-fusion-gnome but it works perfectly under kde4.3.4
i am using fusion icon to call compiz, i am using emerald as a window decorator, not kde kwin or anything similar but i can use gtk gnome

kde4.3.4 running on pclinux 2009 is in a abandoned state, lots of problems raised when many users updated their systems form kde3 to kde4 and it was decided to freeze in kde3.5.10 or in kde4.3.4 and wait for a new iso, pclinux 2010 with kde 4.4.1
this one is in testing state, maybe one more moth to see how it works