Use Partial Open
You can open a document from the Product Structure Editor in CATIA V5. You can also open one or more linked CAD documents along with the document.
The changes done to a product structure using Replace By Existing or Replace By Latest Revision operation in the web, are synchronized to CATIA V5. The synchronization in CATIA V5 happens only if the replaced instance is a part of the Open / Partial Open operation (otherwise an error message is displayed).
From the web UI, you can perform partial open on a document from the Product Structure Editor widget. This action opens the document in the context of its parent. From web search results, you can right-click a filter object, and select Open With > CATIA V5 to open the filter in CATIA V5.
If you have created new data in the web, then you must ensure that you include it in the partial open scope to open it in CATIA V5.