Arrow keys not working with SW Add-In under 64-bit OS

We have built an Add-In that creates its own tab in SW with a data grid displayed on it via the AddControl method. Our customer has found that while running on their 32-bit XP machines they are able to move around the grid from cell to cell for data entry using the arrow keys as we had planned. However, on all of their 64-bit machines, the arrow keys do nothing and they are forced to use their mouse for all movement in the grid. Anyone encounter this before or have any ideas?

Is there anything special required when compiling a SW Add-in for 32-bit SW versus 64-bit SW? Currently, we just have the one Add-in that was designed for 32-bit SW, but has always ran for the customer under 64-bit as well (except for this problem they have just brought to our attention).

(The grid itself is a 3rd party .net control, so I should also investigate that to see if there are any known problems with it or any updates for it.)

Thanks,

Dave Blackburn

CAD fx, Inc.

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