its been a while since anyone mentioned the flood fill tool 'a la inkscape' so I will

ok you can fill unclosed shapes with it up to a point but this is oft times tricky get right

more importantly,for me:

you can fill areas that are bounded by shapes where those shapes are separate shapes - furthermore, these do not have to be grouped or even be on the same layer, as long as they are all selected [may need to change program default setting for this], and the active layer is one of these, the fill is made on said active layer
brilliant - yoiu get line art and coloring on their own layers from the word go

its the same with the brushes - inkscape calligraphy tool is ace for cartooning

so... thank you to xara for the enhanced pdf import and the svg export [though this latter could be improved somewhat maybe?] that enable these programs to interact so well

this is a modular way of working if you wish to look at it that way

So I am not going to ask again for this to be added to xtreme - it is now so easy to port the calligraphy tool lines and color shapes back into xtreme, it hardly seems worth me loosing any sleep over it [and in simple cases of course it all gets done in inkscape anyway ]..