I have no idea what connection would go on top of that bottle, but as an example of the kit you might need to install it have a look at this eBay link (it is an example for a Calor bottle):
https://www.ebay.co.uk/itm/Gas-Safe-Saf ... SwltVeH3a9
I searched using "gas bottle cabinet" and you'll see there are others to choose from according to the size of bottle (which will dictate the gas locker), the regulator fitting and whether you want a complete package.
Although its not shown as an option I've just ordered a top loading cabinet from those people to go in the side under the lifting worktop (I've not gone for the full kit as I have some of the bits already).
And one other thing, if you use PTFE tape to help seal the gas connections I believe you must use the PTFE tape specifically marked for gas use, for example:
https://www.screwfix.com/p/ptfe-tape-fo ... pack/49448
I'm not an expert, and this just my personal experience so far, so for safety please check out the validity of my comments for yourself.
When I've done mine I'm going to get it checked professionally.
Hope it helps.
E D I T - re your mention of a 50mBar regulator - you'll need to make sure anything you put on the end of that is designed to take that pressure. I've just had a look at a couple of ads for hobs and they are specifying 30MBar, a bit more in line with the usual 28mBar or so butane regulator I'm familiar with.
28mBar = 0.406psi, 50mBar = 0.725psi conversion done here:
http://www.convert-units.info/pressure/millibar/28