Access form works with access Viewer but not full version of Access?

I have a mdb file distributed by a vendor my business does work for so that we can upload our invoices to a web-based invoicing system for them to pay. It works fine at work, where I don't have the full version of MS Access, just a viewer of some sort. It's just four buttons - open a file browser and choose an excel file for parsing, check for errors in the resultant parse (part numbers not found, etc), preview the invoice, upload the invoice.

I have the full version of MS Access 2010 at home, and I tried to bring the mdb file home to get some work done, but I can't get anything to work. I'm in form view. The buttons appear to be pressed when I click them, but nothing executes.

I can usually figure this out on my own, but I'm under so much pressure right now that I'm just not getting it. Please help.

I cannot upload a sample due to proprietary information embedded in the file that I don't know how to remove.

New access may render buttons a bit different.
It could also fail if you have llinked tables (to a backend)