Help with transparency

[handrawn]

Being a painting program, painter exports its bitmaps with a background [canvas] because it mimics the 'real' thing - artists dont paint on fresh air [at least, not when sober]. Except: it will save in psd format, which will preserve the transparency on layers; but you need photoshop or photoshop elements or xarapro or paintshoppro - some other program to open the psd that will allow you to delete the white background layer, merge the required layers and export in bitmap format with transparent background preserved.
The good news is that one such program GIMP is free. The bad news is its not a typical windows program, so if youre new to it it may take some getting used to.
It will however import the psd let you delete the white background and then merge the other layers as you wish - exporting as a bitmap with transparent background.
You can download gimp from www.gimp.org - follow the links and the instructions.
Presumably you cant manipulate the psd layers directly in after effects? - not a program I know.