About your crashes...Are you using a CCF that you converted over to the new PCF file? The PENG software seems to have trouble with "groups", so if your old CCF had a lot of groups in it that might be the cause of the crashes. It is doubtful that the new icons in PENG are causing the crashes, so importing your old icons from PE4 won't help on that part.
No you can't import your old gallery all at once into PENG. It has to be done on a bitmap (icon) by bitmap basis. Also you will be loosing the benefit of the 16 shades of grey if you use your old bitmaps (4 shades ).
You will find that if you make a new PCF entirely with PENG that it is actually quite stable (I've had PENG open for several days without having a problem). It seems to be something with the conversion process of CCF to PCF. Also the emulator is a lot more stable on a noncnverted PCF.
Archer