just stumbled across this FREE paint programme for windows, very similar to paintshop pro, as got a few bugs/quirks but hey it's free, should come in useful for anyone wanting to resize their Z pictures
http://www.eecs.wsu.edu/paint.net/
best get the 49mb file which includes the .net files.
tip - when you resize make sure it's set to bicubic as it gives better results.
this is the other way round in paint shop pro - bilinear instead of bicubic