This is a very complex file containing many un- or partly supported features: outlines, images (
http://wiki.lazarus.freepascal.org/FPSpreadsheet#Progress_by_supported_cell_content), macros, filters. Unfortunitely I don't have the time at the moment to focus at this issue, but you could help me if you try to reduce the size and remove features until fpspreadsheet can read it? For example, pages 2 and 3 can be removed, and the bug still exists. I don't know how you inserted the image in the top-left corner of page 1, I cannot remove it. Send the smallest file which still shows the issue. Please don't upload the file to an external server or some "cloud" because the attachment probably won't be available some time in the future, and this makes this thread useless. Upload the file here under "Attachments and other options" (you will have to zip the file, because the forum software does not accept all file types).
As for biffexplorer: No, there is no exe, you must compile it yourself. I just checked it with Laz 1.9 and Laz 1.8 again, and it compiles fine. You must install the KControls and VirtualTreeView (v5.5.3). Use Online Package Manager to get them. (If you have Laz 1.9 you can also use the VirtualTreeView which is bundled with Lazarus now, install it via "Install/uninstall packages")