This is more for practioners but you could have a look at this...
http://www.landregistry.gov.uk/assets/library/ documents/lrpg005.pdf.
If you're not sure of anything let me know and I'll try and help
Watch costs if there is a conflict as it can get very expensive especially if things go to adjudication. At the risk of extra cost an experienced solicitor can provide useful experience and knowledge in assisting these cases and even in negotiation.
Hopefully the objection is groundless but it seems there may be an issue if you have been given notice of it (or did you find out through normal enquiries?).
The Land Registry are fantastic for advice and even as a practitioner I use them frequently for advice.
In the case of a land dispute then you could have a chat with the local police for their advice as to what you should do and how they can help if there are any problems and he tries to evict you.
You could also speak to a lawyer about possibilities of stopping him pending resolution. Some will suggest a letter threatening injunctive proceedings hoping this will stall them but make sure you're aware of any possible circumstances of anything done.
Good Luck!