The only thing that changes between an application and the resulting patent is the claims. No new matter is allowed to be added to an application after submission. I suppose there might be the ability to correct misspellings or grammer, but not content. In the case of the linked documents, the application is identical but if you click on the "Family" tab ...
Espacenet (run by the European Patent Office) and Patentscope (run by WIPO) are both databases through which you can search for patents and patent applications. I believe Patentscope has somewhat greater coverage. In this sense, they are both quite similar to Google Patents.
The European register is the legal register of all European patents and patent ...
Escpacenet's archives are the result of merging the EPO's database and the INPADOC database (holded by WIPO in Vienna). For more information take a look at this blog (not really active lately, but it's a good source).
After 1980, the collection is quite comprehensive. Before that, judging from my searches, it is ...
Espacenet contains many patents listings, you can get patents starting from 1790s more comprehensive coverage list can be seen in following resource provided by EPO
Espacenet doesnot provide search interface for legal representative filed applications. However PAID databases like Orbit, Thomson Reutors total patents etc provide such services.
Further if you wish you can search in WIPO search as they provide search for patent applications filed by legal representative.