You might want to check out the ACEDB FAQ:
Please cite as:
Sherman,B.K., ACEDB Genome Database Software FAQ,
1993,1994, approx. 50K bytes.
There are over 40 different database groups now using ACEDB for there
information some are already doing conversions from ace to whatever.
There are many "tags" of the models that can not be changed and that
data must be associated before the displays will work. For example Map
must be set for a Locus for the genetic maps to display that locus. A
list of these "magic" tags was prepared at the last ACEDB workshop,
some one on the list probably has it.
Some of the references in the FAQ will explain this more. There is
also a "programmers" type guide available, and mentioned in the FAQ.
ACEDB is built on top of a graphics and database library so it is
straight forward to extend ACEDB or produce new applications that read
and write into an ACEDB database.