Aight, we'll have to do things the hard/slow way, then.
> the robots file ignores Disallows issues after User-agent: *
The robots file ignores Disallows issues? AFAIK, the file just sits there on the server and gets fetched by robots, so this statement is unclear. I assume that you mean that Googlebot appears to ignore Disallow directives in the "User-agent: *" policy record, but that it seems to obey them if the "User-agent:" name in that record is changed from "*" to "Googlebot".
Since we can't see the file, a few questions come to mind:
Is there more than one User-agent policy record that applies to Googlebot (i.e. "Googlebot and "*")?
What is the position, relative to "User-agent: *" policy record of the other UA policy records?
Are these other UA policy records more or less "permissive" than the "User-agent: *" record?
Is there a completely-blank line after each UA policy record, including the last one in the file?
Are there any spurious blank lines, say, between a User-agent: line and a "Disallow:" line?
Do all comment lines begin with the required "#" character?
It'd likely be easier to spot the problem with an example to look at, unless you prefer to continue to insist that Gbot is broken instead of making sure that no-one can spot *any* problem --actual or potential-- with your robots.txt file.