How to pull and summarize data from multiple closed workbooks?

Hi all,

I have an interesting challenge at hand. I am sending out a survey to a number of respondents to complete (in spreadsheet form). Upon receiving the completed sheets, I would like to write a macro (or collection of macros) that:
1) summarizes all the data within the closed sheets upon being downloaded to a given file location (i.e. folder on my computer)
2) and checks to see if sheet(s) are present or missing from the summary.

I've included sample sheets that should give you a better idea of what i'm looking for here. I've been attempting this for the past couple of days and keep hitting roadblocks, so any help here would be great. Also, please use comments to annotate your code - doing my best to learn this as I go

Thanks in advance!

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