Index/Indirect/Match Help

Hi
I am trying to develop an Excel 2007 workbook to keep track of various projects. The workbook (attached) has five tabs:
ProjectSummary - a brief executive overview
Timeline - a Gantt chart of the resources for each project
ResourcePlan - A list of projects, with the resource requirements for a particular month
BudgetResourceDays - list of resources and the total usage for a pacticular month
BudgetResourceCostSumm - list of resources with total cost for a particula month

I am trying to develop the Timeline/Gantt chart. For example, the Online Forms project uses rows 5 to 16 (last blank cell in column A) in the ResourcePlan. I currently have to copy/paste the calculation in (eg =SUM(ResourcePlan!G5:G16) etc).

I think it should be possible to look up the relevant rows in the ResourcePlan tab, total them using a combination of MATCH, INDIRECT and INDEX, but I haven't managed to get this to work.

Any ideas?

Regards
Robert