Which version of LO did you have before this?
You stated "3.?".
Win7 has been known to have problems with installing various versions of LO, or at least on my Win7 Home and Professional versions. Win8 seems to be worse, though. These problems are sporadic and there seems to be no real pattern that I have heard about.
Now lets try to fix the problem.
First, see if there is any part of LO that was installed. Go to the Control Panel and Programs and see if LO is listed. If so, remove LO from there. We want to make sure there is no part of any version of LO installed on your system.
Next we should get a "clean" install file, just in case something went wrong during the download of the current file. Hopefully you have a fast connection to the Internet so it will not take too long to get a new copy, and maybe from a different download link or different download site on LO's servers.
Try downloading from this link instead of the "standard one".
http://www.libreoffice.org/download-more/
There may have been a problem with the mirror hosting site that your current version was downloaded from. That has happened before so it would be a good idea to use a "clean" install file from a different download link. To be honest, I need to download many install files and OS versions of LO so I use this "download-more" page to do it.
Do not worry what the top part of the page states for the current versions, since this page is not updated that often. The middle part and the " Other way to download LibreOffice, the productivity suite " linked section seems to be always up-to-date with the current versions.
Download your version of LO and your UK help packs. Try to install it again. If you get an error, try the install once more. Sometimes it takes 2 install tries, or at least I have seen that on my Win7 installs every so often with the different versions I have tested out on Win7.
If all else fails,
I would look at 4.0.6 as an option till someone figures out what it going on with the Win7 Starter install of 4.1.4. I currently use 4.0.6 and have not upgraded to the 4.1.x line, but will in the next month or so if things work out.
Yes, LO 4.1.4 should have most of the know issues of that line fixed by the .4 version, but if you still are having trouble installing it, then I would try installing LO version 4.0.6, which is the last version of that line. If you cannot get 4.0.6 to install either, then there is some issue with your system that is causing the install[s] to fail.