Update to Upfront and Spirit themes completely destroyed layout and CSS

Hello -

We updated Upfront and Spirit theme to the latest versions understanding that we may lose some customizations ( we have backups).

However - the updates completely destroyed the layout and CSS. Furthermore - entering into "Upfront Editing Mode" does not allow us to save any changes. Rather an error appears saying "Your changes were not able to be saved."

So there are two issues:
1. is it normal that the update to Upfront would completely destroy layout and CSS of site? keep in mind we understand that some CSS customizations get overwritten when updating themes and plugins.
2. Upfront editor not saving and returning error

Thank you.