Why Does ad_zd_table.upgrade Convert Triggers To Point at the # View?
I believe now this is by design. The solution is to point the source code for insert/update/delete statements at the editioned # view of the table. Then the triggers work. Alternately, you can create a synonym and point the insert/update/delete statements at the synonym. I'm not sure which is a better solution--although everything I see on the web is recommending the synonym approach. (Specifically putting the synonyms in the APPS schema. You can't put a synonym with the same name as the table in the same schema as the table, but I'm not sure why the APPS in particular is recommended, or why the synonym approach is recommended. If anyone knows the answer to that please comment.)

For more info:
Oralce: Why Do Triggers on Editioning Views in My Custom Schema Fail?