>Being an oracle knower i was very interested in firing trigger recently i throughly implemented it in my indent and export documentation software i.e. almost all my complex updates are been doen by triggers uptill 3-5 levels.

This is a very difficult problem for someone besides yourself to solve, especially with your nested triggers.
The best advice I can give you is to wrap your TABLEUPDATES in a function that checks for their success before you try to move the record pointer or close the table. If a TABLEUPDATE fails, you can check for update conflict with AERROR, and then check for which fields have been modified.

You will have to analyze your triggers very carefully to check the sequence of tableupdates, and lay out which routines could be the cause.