@Tinus sorry for the delay, I went on vacation and have not been able to get back to the issue.
To answer your question, these are custom notes applications that open fine in Windows clients and non 64 bit mac clients.
The behavior is upon attempting to open the database by using either workspace link, File - Open - IBM Notes Application, or an action hotspot with @Command( [FileOpenDatabase] ; "server"; "database.nsf") you see the database is open for the user on the server but nothing is displayed in the client..no new tab that hints that the database might be open, nothing to make the user think the database is open but it is. Immediately after attempting open if you do File - Application - Properties then you see the application properties for the application that is "not opening".
I found another interesting work around for my issue. If I use a URL hotspot with notes://server/database.nsf to open my databases that are seeing the issue I can consistently open them and database content is displayed. Scratching my head! Why would a File - Open - IBM Notes Application or an action hotspot with @Command( [FileOpenDatabase] ; "server"; "database.nsf") show inconsistent behavior upon open? Sometimes opening and displaying content while at other times opening but not displaying content????? I reported to IBM and they have escalated to Application Integration.