What works
Conditional formatting; ribbon (flawlessly); thesaurus (even without me knowingly installing wsh56js); opening and saving files (after protected mode had been disabled and msxml6 installed)

What does not
Some things which are drawn over the sheet are not correctly hidden in certain circumstances. These all correct themselves when the affected cells are scrolled out of view and back in again. The examples of this which I have come across are: Comments: After adding or editing a comment, the sheet underneath the comment text box is hidden by a black box. After viewing a comment by hovering over its cell, the gridlines behind its box are shown black. Selected cells: When something causes a cell to be redrawn (e.g. content change, color change, etc.), the gridlines under the selection rectangle are redrawn in black. If a range is selected and modified, the selection rectangle's colors will invert. Clicking away will make the selection rectangle stay visible, with the selected cell just a black box. To begin with, the list boxes in the Format Cells dialog would not change their selection when clicked, but they mysteriously started working after roughly ten minutes of testing. I restarted Excel at this point to try and break them again, but they still worked after the restart.

What was not tested
Anything not mentioned above.

Additional Comments

I had to restart the computer before doing these tests, otherwise Excel would crash after about two minutes of use.