Pull numbers from closed workbook

I need code that will pull values from a closed workbook. The path will be variable based on the value in a cell. I'm currently using the indirect.ext from the morefunc add-in but I want to get away from that so I don't have to install that add-in for every new person who uses the file.

I attached a mini example of what I want to do. You can see that each box has a carry forward amount that it gets from a closed workbook, a number that it changes by, and then the new total, which will be carried on to the next file. The formula is set up to automatically look 2 spots below its current location so I can cut and paste each box to a new location, or copy a box to a new location and it will work without having to change cell references. The example files are made to work in C:\Temp2\

If anyone can help me make a code that will replace the indirect.ext I would be eternally grateful.