The earlier sample file i attached used your Collection approach only. Dictionaries can store any datatypes including Objects (not sure of Picture types if they are not considered as objects...).
I am also using the same declarations that you provided, but still the same issue. The only way it works, is as shown in my earlier reply, i am able
to load the pic directly i.e.
Thisworkbook.sheets("PicSht").Image1.Picture=IPic
but not by assigning from a Collection
PicCollect.Add PastePicture(CF_ENHMETAFILE)