Hello,
"I can get it to work somewhat if I add the following code..."
Well, done ! I will update again our Docuemtation, thanks for this hint!
"Now the select drop down in characteristics is not showing correctly with this code."
=> Yes, I was a bit quick with my solution, sorry for this, just add the class ".form-check.form-check-inline" to your div in order to restrict this command to "checkbox" style options.
table.hikashop_product_characteristics_table div.form-check.form-check-inline {
display: inline !important;
padding-left: 5px; // optional
}
Hope this will helps.
Regards