so I know what I was doing when I flashed this one
How did you flash exactly?
If you did not use the flash.bat file (included in the BIOS Archive), did you use the proper flash command switches when you initiated the flashing procedure (/E is of major importance here, as tells the flasher to update the EC-Version along with the BIOS Version). If the BIOS was updated but not the Embedded Controller, this usually leads to an updated system BIOS that is incompatible with the (much older) EC Version which is left over by the previous BIOS that was used).
I bought this system off craigs list brand new so I have no clue really were it came from. Has a spanish looking keyboard I had to re-sticker it so I know what keys are what.
Are you one hundred percent sure that the netbook you got was actually a genuine Wind U100 (Retail Version) and not some OEM-Variant? There are lots of OEM versions around and the problem is that some of them use specific OEM BIOS Versions. In many cases the Retail BIOS Releases from the MSI Product sites do not properly work on the OEM Netbooks.
Do you, by any chance, remember the full ID of the BIOS Version you used before the update?