Hi!
So now we know, what to do.. While copying these elements, its best to first download the xml and then upload this xml in new SF.
If you want the whole SF to get copied. Click on "Download Form". If you want to copy only a part of SF, then double click on the node you need to copy then click on utilities => "Download Subtree."..
Also if you dont want the content of SF into next page, then add the same elements (text. windows, etc) in a secondary window and not in Main Window.
Regards,
KS
PS: http://wiki.sdn.sap.com/wiki/display/ABAP/WINDOW+TYPE+IN+SMARTFORMS