Trying to troubleshoot CS5 on Mac OS X (10.7.2) Update question

Question

I know I cannot be helped unless I provide appropriate information. I also understand that it is important to have all updates. So, before I even get to the problem, I checked my version of PS and it is 12.0. I believe 12.0.4 is where I should be. Alas! When I go to updates in PS, it brings up Adobe Application Manager which assures me that I am up to date. This is false. I have asked it to refresh itself and check again but it continues to return the erroneous message. I went directly to Adobe and downloaded AdobeUpdate.dmg and tried to update that way. Again, Adobe Application Manager launches, plays with itself a bit and then advises it was unable to instal the update, I should fix the problems listed below and retry. It helpfully reports the problems as Photoshop 12.0.4 installation failed.
Hmmmm. I am hoping someone has some idea so I can update and then come back and get help with my actual problem.
(Insofar as that goes, PS has decided lately to run out of memory, to choke on reading brushes, to crash on a fairly regular basis. In short, has turned my normally wonderful time spent happily in the program in complete and total ignorance of all things technical into a nightmare in which I am starting to hear HAL's ominous voice in the background.  Since my technical knowledge is so sketchy and my troubleshooting technique less than stellar so far, I was hoping to copy the next error report, post it and pray someone could provide an interpretation. But I am suspecting that the first order of business will be to update and come back.)
I know that subject lines such as "Puuuulllleeeezzze help me!" are frowned upon as uninfomative and overly dramatic so I saved it for the end instead of the beginning.....

Answer 1

I checked where suggested. I originally checked it in About Photoshop. Doesn't matter: both places report that I have 12.00
I have 4GB of RAM, I have 194.9GB of space left on on my hard drive, (I have an empty 3TB EHD as my scratch disk), my average file size is 150MB, I load brushes as I need them and do not keep them loaded (I run a set of parallel / mirror folders where I keep all of my stuff be it actions, brushes, swatches, patterns and the like separate and outside of what came in the PS box, so to speak and I load only on demand. The vast majority of time, I reset the tools etcetera at the end of a session). I am thinking that I may have a third party plug in problem and I am using an Adobe Article on trying to troubleshoot that while waiting for PS to crash again to give me my error report. I do have a lot of third part plugins but I have done this exercise before (tedious) and thought things were well in hand. I am only guessing.
The summarized error report is that PS unexpectedly encountered an unrecoverable RAM problem--at that point, down I go. In the interim I am saving on a constant basis but short of saving after every brush stroke, I am inevitablly losing work, hair and sleep.
I wanted a read on the logged error report because I feel like I am trying to troubleshoot on too many fronts: is this a 32 vs 64 problem, a third party plug in, an error that has been corrected by the update etcetera. Of course, in the last few hours I have been trying to solve stuff so I haven't been using PS so I don't have an error yet. Working on it.