PENG seems to be a memory hog. Opening the first PCF file it took 27 meg of my memory, opening a second PCF jumped the memory useage to 40Meg. Closing the second PCF only released 3Meg of the memory. Reopening the second PCF jumped the memory useage to 47Meg. By comparsion Office word only used 10Meg of memory when opened.

If your ME machine has lots of memory, no problem. Less than 128Meg of memory and you will have performance issues and lockups.