I use async updates for a refresh of data in a db grid for obvious reasons...

I'm changing the color of some cells based on the 'age' of the row using OnGetCellProp... i.e if an appt is past due, etc.

This is only called it seems on SYNC page refreshes... and therefore the color is set to the default for ASYNC refreshes... is there a mechanism to set the cell properties for ASYNC calls?

Since the data might change of course between ASYNC refreshes... I can't figure a way to use a cell tag ID...

Unfortunately the OnGetCellProp event currently doesn't support asynchronous updates.

This is on our feature-request list to be implemented in a future version of the IWAdvWebGrid control.

Is there a work around you can suggest to customize the look of individual cells?

Can you try using SYNC page refreshes instead of ASYNC refreshes?
This would allow you to use the OnGetCellProp event.