I have now gone through the paperwork you have provided.
I confirm that 152 does not benefit from any express right of way (ROW) over the Garage area. If there was such a right, it would be mentioned in the Property Register of your Title being numbered SGL111015.
Likewise, there is nothing in the title (410822) to the garage area stating that 152 has a right of way.
As you have no express ROW, you would need to seek permission from Mr and Mrs Wentzel to use it UNLESS you can prove that your property known as 152 has had the benefit of unrestricted access over the garage area for 20 continuous years or more. This use must have been used frequently (normally at least 20 times a year), without dispute and without any express consent of the owner of the garage area.
If you are able to swear a Statutory Declaration confirming the above, your property has acquired an "easement by prescription", meaning that a legal right of way has been created, and that right of way can continue. Although such a right exists automatically after 20 years, it is best to register the easement at the Land Registry. You should consult a local Conveyancing Solicitor to do this for you as there is a set application form to be submitted.
I hope this assists and sets out the legal position.
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