The formula you provided, =AND(ISNUMBER(A1),ISNUMBER(FIND("!",FORMULATEXT(A1)))), appears to be a valid formula.
One possible cause of this issue could be that the conditional formatting formula is causing a circular reference or other calculation error when applied to the data table.
This could cause Excel to crash or become unresponsive.
To fix this issue, you could try modifying the conditional formatting formula to avoid any potential calculation errors or circular references. You could also try disabling automatic calculation for the workbook while creating the data table to see if that prevents the crash from occurring.
If these suggestions do not solve the issue, it might be helpful to provide more information about the specific steps you are taking to create the data table and apply the conditional formatting.
I hope this helps!