Yes, Opencart Marketplace supports all kinds of responsive themes, templates,s and custom themes/templates. After the module installation, the features of the module will reflect perfectly on the theme/template. If in case, there is any theme compatibility issue, we will surely fix that issue for sure.
If you have added a Journal theme with our Opencart Marketplace then your front end will be displayed as shown in the link provided (http://journal2-203-122-41-218.ocdemo.webkul.com/).
Please do contact us for any further queries or requirements. You can also check our Opencart Extensions for additional features.