Before posting, please read the Posting Guidelines. Failure to follow the guidelines can result in being ignored!
There also is some help there for using the Vanilla Forum.
It looks like you're new here. If you want to get involved, click one of these buttons!
The plugin generates a fixed width container of 640px wide with sub container also fixed width of 635px, and all images have fixed sizes, so the only way it can get bigger is if you have a setting to make the plugin create bigger container. Ideally to be responsive it should generate all it sizes in percentages
because it is not responsive (does not adapt to reduction in browser width) so il will surely cause problems on mobile.
If the options are not there in the plugin, they would have to add them in, or you would have to find a better plugin that is responsive
You should bring it to the attention of the developer and see what they have to say.
Not being responsive is becoming a serious flw in a plugin, it is in their interest to change that.
I am also surprised they would not have a setting to change the width of their content, even if not responsive (dynamically adaptive), they must be allowing some way to decide what fixed width to make their content.