Thanks all for the tips, I'm actually trying anything and everything at the moment
Yes I have tried downloading a few times the zip (to make sure it wasn't corrupted), I also tried (which is what I normally do) with wget (ssh), I tried uploading in many different ways. I uploaded the zip file with FTP, also the unzipped file via FTP, even with terminal scp.
Nothing seemed to work, I contacted my host last night, they tried and tested obtaining the same result, they're still on it and have asked me to stand by until they find the problem. It seems to be a combination between Suhosin and XPDO and who knows what else.
As soon as I get a positive response from them I'll post some feedback.