AppleScript? - Numbers App

I utilize [login to view URL] to maintain a time entry system for my consulting business. I mark time throughout the day and then at the end of the day (or week) need to group and aggregate my entries. As part of that, I need to combine my task description, total the amount of time and then quantify to the nearest tenth of an hour. Attached is a sample of what a portion of a day looks like - tab one being the raw entry - tab two being what I want it to look like when done. I would like to automat as much of the conversion process as possible (i.e., grouping by client; creating total time (rounded to nearest tenth and entering in column D); combing task descriptions into one box and eliminating excess lines). Note that the total number of lines per client will vary considerably (from one to dozens in a given day). I'm open to changing to Excel or some other platform but need to retain the basic structure (client, description, start/stop time)