Updating the Model With Comments from Excel

We have a large database (~500 tables) modelled in Vertabelo. We have some existing documentation of table descriptions and column descriptions in an Excel spreadsheet. We would like to move our documentation from the Excel spreadsheet into the Vertabelo model. Can you suggest the best way to do this?

We looked at the API but that appears to be read-only. We have considered exporting the model as XML and writing code to update the XML file from the Excel spreadsheet and then re-importing the XML but this involves a certain amount of time to write the code to do this.