You could try out the DAFNE app (search for "DAFNE ONLINE") and see if that was any better for you? it's less visual but it does things in terms of, eg., 1 scoop of mash that weighs 60g = 1CP.
Not sure if you've done DAFNE but if you haven't, a CP is just what we used to call a carb exchange, i.e. 10g carbs.
I think it's free, or at least it was when I downloaded it, if memory serves. Let us know if not, and if it works for you.