blocks purge

Hello  ALL

1) Is there any way to open blocks created in SolidWorks version 2012 to 2011?

2) In solidworks drawing I have added many blocks & some blocks are deleted. When I save file and restarts the same one I find that even if deleted blocks appears undee design tree blocks.

3) When I delete block from design tree & it has more than 1 instance then it deleltes all the instances of that block

is there any way to restricting this activity.

Kindly guide me for the same.

attached screenshot

-sanjay

SolidworksApi macros