Hi,
1. I see that you entered the URL of the images in your CSV. This means that for each product, your server has to download the image, store it and then store the product data. Downloading the images takes a lot of time so if you have a lot of products in the CSV, it's likely that the import process will hit the max execution time limit in place on your hosting and you'll get a 500 error.
To avoid that, you can either increase the max execution time setting of your server, or upload manually the images in the folder images/com_hikashop/upload and then specify only the filename of the images instead of the URLs in the CSV. That way, the import process won't have to download and store the images, it will just have to store the data in the database, which is much much faster.
2. If you have products that you can't find on the products listing, ir means that they are not linked to any category or that they couldn't be imported.
Try clicking on the "check database" button of the HikaSHop configuration. It will link all the products without any category to the main "product category" category so that you'll find them there.