First, 8.60 is PSQL V8 SP2. PSQL V8.7 is SP3.
Second, why are you needing to do a trigger? In PSQL, once a trigger is defined on a table, Btrieve access is disabled. For example, you list an "AFTER UPDATE" in the CREATE TRIGGER. Once this trigger is created, Btrieve applications will not be able to update that table. Only SQL based apps will be able to update the table.
Post your actual CREATE TRIGGER statement. Pseudocode won't help if there's a syntax error.