Hello there; You do not need to check for conflict before analysis. If you have modeled including combinations, you can analyze and design. Conflict check is done before drawings are created so that there are no errors during manufacturing. In terms of steel, on-site manufacturing is important at the mm level. For this reason, if there are elements in your project that you have not entered into, or there are cases where the plates of the joints or the roof cross and purlins overlap, they must be corrected. Good work.