Did you add a comma after the userid field?
Userid => [9,'alpha', -2,15,0,'',''],
and then add you new field:
Name => [10, 'alpha', 40, 255, 1, '', '']
as the last field it would not end with a comma.
There is an excellent DBMan tutorial on JPDeni's web site
If you plan on adding an extra modifications later you will most likely want to create your own displays and not use autogenerate.
Let us know if this helped.
Unoffical DBMan FAQ
http://redundantcartridge.com/dbman/