More tips required

I suggest doing away with the adapter and getting your car wired to a 13 pin set up. 

You can buy breakaway cables in any caravan accessory shop. 

I can’t work out what you need an extension cable for. 🤷🏻‍♂️

Sorry if I wasn't clear -

the car has a 13 pin supply

the caravan is a 7 pin socket

the adaptor is needed for the interface between the 2.  We will upgrade at some point, ther 13 pin option seemed the best long term choice.

When i wire up thre new 7 pin socket, i don't want to need to move the caravan in front of the car when checking the connection.  So, a long, loooooong extention from the car to the caravan?

Ta

ESC the first thing I will say is don't worry about this; this type of thing has happened to  all of us.  May I suggest that you prepare a check list, there is one in the Club's handbook which covers everything.  Moving on to you questions:

1 and 6 - these are linked points.  I assume there are 2 x 7 pin connectors on the caravan; you refer to only one connector from the caravan!. When both 7 pins are connected the various lights etc should work, if they don't then the wiring is wrong and needs checking.  If you need new connectors any dealer should have them (think Halfords also have them). There is a wiring diagram in the Club handbook. As you say you should be able to do this yourself but if it does not work after any corrections a quick trip to a tow bar fitter may be necessary.  You should not be able to connect the adapter to the car 'in the clearly wrong position'!  All the connectors should fit together in the correct position only.

2 and 3.  Yes, replace the breakaway cable.  They are quite cheap and available from any accessory shop,  Just make sure it is threaded correctly through the guide 'hole' in the A Frame - look at the existing one and follow it should be in a straight line from the bottom of the brake to the end of of the tow bar.  As the cable broke all should be ok on the caravan, just check the operation of the handbrake.

4. No

5.  Most people have 2 bottles of the same type to be on the safe side.  No need to have the different types of gas and as you seem ok on Butane just get another bottle - this may be a bit difficult at the moment but supply should be sorted soon.  I have 2 x Propane to cater for any temperature.  

You did exactly the right thing going on a local holiday first.   Don't worry you will soon get used to packing and ensuring all is ok.  Getting distracted is fairly common so if it happens again just start your checks again.  When I have done everything and connected up just before I depart I walk around the caravan checking everything again - Stabilizer on, handbrake off, breakaway cable connected, corner steadies up, all external cupboards closed and locked, Mover off wheels (lost track how many times I have tried to drive off with mover on wheels and I have bee caravanning for many years!), door locked and finally all lights on caravan working ok.n

Wire the caravan to a 13 pin plug.....very easy.

Best to make a join between the 13 pin and the 7s inside the van, rather than trying to wire 2x7 cables into a 13 pin plug

Just seen your second post.  Are you sure the caravan has only one connector.  There should be 2!!!!  Not sure what you mean about moving the car when checking the connection.  You should have hitched the caravan to the car before connecting the electrics etc.  If you mean to check all ok after you have done any wiring alterations - well sorry but that is what you have to do, but you then know all ok so just the every trip check I mentioned in my post above is all that is needed.  Suggest you ditch the adapter and wire the caravan side to a 13 pin connector.  You should have no need for a very long cable and anyway wiring it up would be difficult.

if the caravan has just the one 12N plug, I'd suggest using one of these instead of the long lead than can drag along the ground. Make sure you buy the right way round as you can buy 12N to 13 or 13 to 12N

I agree, but there are 13 pin plugs with a double cable entry gland 🙂

https://www.ebay.co.uk/itm/323329059192?hash=item4b47e9e978:g:BB0AAOSwFN9d1QJ6

If you are getting a second gas bottle don’t forget to check that the nose weight of the caravan does not exceed the maximum for the actual hitch (if Alko usually 100kg) or the maximum loading for the car, some are as low as 75kg even for some bigger cars. My caravan has fittings for two gas bottles but it is very difficult to get the nose weight low enough if I have two bottles in place and I have a car with a 90kg maximum. Checking should, of course, be after you have put everything else in the caravan and ready to set off. For safety and outfit stability it is usually recommended that the nose weight is as near to the maximum as possible but without exceeding it. Incorrect loading is one of the main causes of caravan accidents.