Try going to File - Purge Memory
Make this your habit - do it every few minutes.

on the bottom right of your screen it has a listing that says "polygon count" - click the arrow beside it, and it should bring up a drop-down list.   click on "free resources" to bring it up instead.

Now, whenever this drops below what you feel is good (for me with 6 esprit, it was at about 45-50%), go hit that purge memory =D  (and dont forget to save!)

Rarer than a hairy egg and madder than a box of frogs....

< o > < o >    You've been VUED!    < o > < o >
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         O                                                    O