Yes, several people are in your situation. We designed CalendarBudget so the categories span accounts since most people are using CalendarBudget for their personal finances and thus it makes more sense this way. However, when you have an account that should have distinct categories, we recommend you create distinct categories for this separate account. Here, how I would do it:
Preface all my categories with something like “Personal-” or shorter “P-” giving:
P-Auto
P-House
P-Entertainment
etc..
Then for my business categories, preface with “Business-” or shorter “B-” giving:
B-Auto
B-House
B-Meals
etc..
Then when categorizing individual transactions, make sure to use only business categories in your business account, and visa-versa for personal items.