Without invoking VBA, I'd be looking at Conditional Formatting, Index and Match functions. Really need to see a sample of what you are trying to do.
Using Office 2010 gives shedloads of CF options.
A combination of something below might work. Not an expert, but use these to track last date of an event and how much done on a particular day.
=INDEX($A$13:$A$377,MATCH(9.99999999999999E+307,B13:B377))
=LOOKUP(9.99999999999999E+307,B13:B377)
Date down the left, numbers in the next column. columns to the right can be added as required.
You can section the SS into date areas and build a graph(s) from there. High maintenance, really, when you could buy a prog from T'internet for a few spondoolicks.
Conditional Formatting, combined with a separate, linked, area on your SS to highlight bit and bobs, with a graph based on that, may be your easiest answer, though.
PS. It's after midnight, might not make sense
