Should I have known what would happen, i would never rush to update just for year-end reports. Since we have opened so many company files and entered an amount of transactions in the 25/26 version, it's impossible for us to revert back. Though about your method, but it could be another nightmare. 

For those who have not done so like I did, reinstall the 24/25 version and copy only the files for tax table and forms from the 25/26 2.03. This is so far the only and best solution. So much better than the unstable, unreliable, and unresponsible official updates.