It's more likely that your database doesn't support the functions you used. For instance (if memory serve) COUNTD() is supported by Tableau Extracts, but not supported by some data sources. (I can't remember which ones at the moment.) Once you've converted the data source to live, then open your broken calculations and you'll see the errors.
Do you think that renaming the Dimensions name in the Tableau Data Pane might be the reason for calculation in validation? I am using Custom SQL.