#How can I display the cross sell as a slider/carousel?
Settings-> Cross-sell display settings -> Display cross-sell slider.
#How can I hide fully sold-out cross-sell products?
To hide the sold-out cross sell products:
Go to Settings-> Cross-sell display settings -> Display sold-out products.
#How to limit the number of cross-sell showcased per product?
Settings ->Cross-sell settings ->Maximum Cross-sell displayed per product.
#How can I customize the look and the colors of the cross-sell to match the store theme?
The look and feel of the cross-sell can be changed using the custom CSS codes.
To do it, Go to Settings -> Custom CSS.