Hi Wishgranter
Thank you for your tip but I'm not using windows. The problem, in my case, exists in MacOSX. If this is a feature and can improve PS, no problem. As a matter of fact, all my tasks seem to be better accomplished in this latest beta, with great final results. The problem seems to be related with disk memory release. This version tends to cumulate used disk memory without releasing it. Alexey Pasumansky already enlightened me about how PS now handle memory but, even considering those good reasons for memory use, I think that there's some space for memory release routines for finished tasks.
Cheers