The issue is that you have not defined the Scale and Precision of your Oracle Number() type. An Oracle number that does not have an explicitly defined scale and precision has a range that is crazy large.
It is not that dbFront can't display large numbers. But many users who setup Oracle don't appreciate that by not defining a Number(), they are setting themselves up to work with numbers that have a range of 1.0 x 10(-130) up to but not including 1.0 x 10(126).
This would mean that I would have to setup a multi-line field to cover the 132 possible digits that a user could enter for each of those numbers when the user is likely only expecting to enter something like 123.45.
To deal with that, all Oracle numbers without a defined scale and precision are treated as Number(16,4).
The dbFront logfile also creates a log entry for all undefined fields explaining what it has done.
The request is that you just define the oracle numeric type and set a reasonable range.