I'll address inactive memory momentarily. But first let's review what you seem to already know are the central issue:
You have a lot of paging going on, and epecially a lot of page outs as you observe. Your free memory is very small, suggesting a memory shortage.
Inactive memory can in fact be useful if it is not active at this instant, but some app is about to use it, perhaps repeatedly. Inactive memory in and of itself does not necessarily indicate a poor memory deployment.
If your Mac happens to be one of those that could accept a memory boost, it might well be worth the investment.
Best of luck! Yours was a very interesting question to consider.
By the way, your second post arrived after I posted my response. So it looks like it takes a while for the memory issues to build up. That's really not too surprising, but you show it quite dramatically in the differences in your sets of numbers between your first two posts.
Bottom line: Don't allow Enfocus support to give you an answer based on any short duration testing they may perform.
Page outs should only occur when you re out of physical memory and thus the system uses your hard drive as a scratch disk to write to. The fact that the amount of active memory is so low compared to the amount of physical memory available, given the the size of the page outs, indicates that your inactive memory is not being freed correctly (a memory leak essentially). This is most likely not a hardware problem but a software problem having to do a particular program.
"Inactive memory in and of itself does not necessarily indicate a poor memory deployment."
This is completely true as stated by sberman. Page outs + large inactive memory is poor memory deployment as your RAM is not being efficiently utilized.