Datagrid: dgFormattedHeight geometry question

[David Bovill]

I'm having problems with the geometry of a datagrid - I have a row template
of variable height with a disclosure toggle arrow - much like that in the
Webinar. The problem is that the row templates at the bottom of the
datagrid, when expanded do not increase the range of the vertical scrollbar
of the datagrid resulting in records which you are unable to scroll down to
view. RefreshList has no effect. The script I use to toggle the row
templates expanded info group is:

on DiscloseView someBoolean
>    lock screen
>    put the rect of me into oRect
>    set the visible of grp "Toggle" of me to someBoolean
>    LayoutControl oRect
>    RefreshList
>    unlock screen
> end DiscloseView
>

I am guessing that this technique does not properly change the
geometry/dgFormattedHeight of the datagrid - but before I try teh technique
used in the Webinar (adding a visible entry to the dgArray for each record)
- I thought it would be worth checking what is going on here - or is this a
bug?