[AccessD] Access 2010 Data Macros

Hi group,
Any of you been playing with this new feature?
Data Macros in A2010 is supposed to function similar to triggers in SQL Server.
So I expected the feature to be able to automate something like this: cancel an order detail record if the item amount exceeds the stock available in a stock table.
Which doesn't seem to be the case: the functions exposed narrow down to the very few standard Jet-functions and doesn't include the needed Access-functions for lookup and aggregation.
And worse: Can't get this feature working for me at all. Tried a simple exercise reproducing the simple example in:
http://www.youtube.com/watch?v=J3G0ivjpy9k
- result: nothing ...
So any experience with this feature is appreciated.
Asger