When you create a new custom Form in DCRM you can then go in and add Marketo Sales Insights onto that Form.
Step 1: Edit the form you want to add MSI to to first add a tab, and then a web resource
Step 2: Select the mkt_/PersonView.htm web resource:
Step 3: Adjust the formatting for the web resource so it is one column, and the height is 12 (not 6)
And that should do it for you!