Vuetable-2: Property or method "css" is not defined on the instance - laravel

Question

I'm trying to get Vuetable-2 to work in our solution. The demo works without problems. The difference is that we use a lot of different modules and I'm fairly new to front-end development and fail to see what the problem can be.
The difference between the demo and trying to set the demo up in our own project is this:
Demo
import Vuetable from 'vuetable-2/src/components/Vuetable
Our project
import Vuetable from 'vuetable-2/src/components/Vuetable.vue
The reason for doing so is because if I do not (leave out the .vue), I'll get the following error:
ERROR in ./~/buble-loader!./~/vue-loader/lib/selector.js?type=script&index=0!./resources/assets/js/components/VuetableTest.vue
Module not found: Error: Can't resolve 'vuetable-2/src/components/Vuetable'
But, with the extension in the import, I'll get this (in the browser console):
[Vue warn]: Property or method "css" is not defined on the instance but referenced during render. Make sure to declare reactive data properties in the data option.
(found in component <vuetable>)
[Vue warn]: Error when rendering component <vuetable>:
Uncaught TypeError: Cannot read property 'tableClass' of undefined
Now I have the feeling it has something to do with me needing to add the extension to the import, something that is not done within the Vuetable files, for example import VueResource from 'vue-resource'.
Our package.json:
{
"private": true,
"scripts": {
"prod": "gulp --production",
"dev": "gulp watch"
},
"devDependencies": {
"bootstrap-sass": "^3.3.7",
"gulp": "^3.9.1",
"jquery": "^3.1.0",
"laravel-elixir": "^6.0.0-11",
"laravel-elixir-vue-2": "^0.2.0",
"laravel-elixir-webpack-advanced": "*",
"laravel-elixir-webpack-official": "*",
"lodash": "^4.14.0",
"multiselect": "^0.9.12",
"node-sass": "^3.10.0",
"notifyjs-browser": "^0.4.2",
"sweetalert": "^1.1.3",
"vue": "^2.1.0",
"vue-resource": "^1.0.2",
"vue-router": "^0.7.13",
"vuetable-2": "^1.2.0",
"vuex": "^2.1.1",
"whatwg-fetch": "^1.0.0",
"wow.js": "^1.2.2"
},
"dependencies": {
"laravel-echo": "^1.0.5",
"pace": "0.0.4",
"pace-js": "^1.0.2",
"pusher-js": "^3.2.1"
}
}
If I need to provide more information for anyone to even begin to try to help me, please let me know, as I do not quite grasp in what direction I need to look.