Problem with CachedUpdates and local Paradox tables.

I have a query on a local Paradox table which I am displaying in a
DbGrid. Upon selecting a row in this grid I am displaying a small screen
in which to make changes to this record. The Query is producing a
readonly result and so I am using CachedUpdates and an SQL Update object
on that Query to do the actual update. However, my changes to the record
and not permanent. They are shown in the DbGrid, but not when I exit out
of the application are restart it.  I am using ApplyUpdates and
CommitUpdates on the query object. It would appear that the SQL update
object isn't even being called!. I even created an OnUpdate object for
the Query, which isn't called either. It's weird as it works when I set
the requestlive property to true. Surely CachedUpdates in this situation
should work?. I don't often use RequestLive as it is. I should also add
that I am using a DataModule.

Does anyone have any ideas what I am missing or doing wrong?.

Thanks

Nigel.