Hi Robert,
Thanks for your response!
Currently we don't have an option to disable diagnostic (including error messages for undefined functions, undefined variables or other syntax errors). We are considering to add some settings to enable / disable this in future release.
If you don't setup related settings (include, catalog, accounts, etc.), you can still use all features.
But in some cases, some features could not work well.
For example, if you defined a function / variable in file A, and it's included in file B. When use "Go to Definition" in file B on this function / variable, the definition may not be located correctly. Because the extension may could not find file A' s location if it's not configured. I guess some errors you encountered belong to this.
Thanks