based on the filename of
'    the items being added.
' 5) Allow load of GIF, CUR and ANI from the property page.  For .ANIs,
'    you can choose whether to load just the first frame or import
'    all frames.
' 6) Allow bitmap transparent colour to be automatically determined
'    for bitmaps and GIFs (nb: use of JPG is not recommended because
'    JPGs do not maintain colour stability - any area of transparent
'    colour will vary approx +/- 3 colour values from the actual colour)
' 7) Bugs causing the co