@itsme The design is such that a single row in a csv file is considered one Profile or Event. Therefore mapping multiple rows in a csv file into one Event isn't possible. This is far easier in JSON structure, I'd highly recommend using that.
Given that, if you have no other option... trying to think outside the box, don't know if this will work and never done this. You may want to play around w/ multiple pipe delimited fields and see if that can work. It will be tricky and require a lot of debugging (and I don't have any sample code for you). The idea would be passing in for each field in the Object Array:
Product ID = "123|456|789"
Quantity = 4|1|9
etc.
File looks like this:
[_id],[identity],[Product ID],[Quantity],[etc.]
Then you would have to create a calculated field for each element and map each element to the correct element in the target. i.e. you hard code it.