adding ranges and opening workbooks with variable names

Howdy,

this is propbably an easy one but i cant seem to work it out .

Background on the situation:-
this is a daily totals sheet but alot more complicated which i cannot post due to the shear amount of personal data. what im trying to generate is cumulative totals in its own report which can be updated on a monthly, quarterly, annualy and financial year basis. Each report is its own workbook with a variable name. I need to take data from the daily sheet and put it into each of the reports as in the example below. after which the daily sheet is saved as the date and then the original reset to blank for the next day.

basically i want to add a range of cells from 1 work book to another same sized range in another work book ie. A1(rng1) + A1(rng2) = A1(rng2) new value

A1(rng1) + A1(rng2) = A1(rng2) new value 
A2(rng1) + A2(rng2) = A2(rng2) new value 

where rng1 is in the original workbook and rng2 is a cumulative total of rng1 every time the code is run

^ this is obviously not the code

ive got the saving of the workbooks, the saving of the daily and the reseting of the daily workbook sorted. what im needing help with is the coding for recalling the workbooks(path- (C:\Temp\"Variable Name") the names are saved into a sheet called "Worksheet1" that is never reset which has all the rates and counters etc in it) and then the addition of the ranges as above.

Once again my apologies for not being able to post example workbooks and i hope all that makes sense if anyone is interested in helping me out with any part or would like further information please PM me and i should be able to explain in a bit more detail.