I also screwed up with the 1.12 Bios version for the Acer Travelmate 2200. But, fortunately everything works again. With a lot of googling and going to this site, i finally got the solution. What you've got to do:
1) Get a USB floppy drive. (you get them for little money on second hand auction shops and a clean floppy.)
On another pc:
2) Download the v1.07 version from the Acer ftp site.
3) Download crisdisk.zip (mail me if you can't google it)
4) unzip this file on c:
5) rename the bios v1.07 file to BIOS.WPH
6) put this file in the crisdisk project folder
7) Use crisdisk tool to create a bootable diskette and a bootable floppy with the files phlash.exe, minidos.sys and (the 1.07 bios file) bios.wph will be created for you

Put this floppy in the floppy drive connected to your Acer.
9) Make sure your travelmate has no battery, put in the AC-plug and hold the buttons 'Fn' and 'B'.
10) Push the power button, with the two other buttons still down.
11) If the power led start, release the 'Fn'and 'B' button.
12) If you're lucky, you'll hear lots of beeps.... Your computer will reset itself and start in Windows!!
If the booting doesn't succeed, try a different timing on releasing the 'Fn' and 'B' button.