I've written custom software (which was a lot harder to find than some python WMI hooks) for hacking a lot lower profile organisations. I've consulted for organisations that were hacked by Chinese hackers for bitcoin ransom that had custom software written too. I mean, high profile target, more effort can be expected. It does not mean the government is involved (although a lot of hacking groups seem to have government sidelines in China, though it does not appear to be their primary activity. I mean unless the Chinese government is itself into bitcoin ransoming).
But more seriously, if a component of our government that is this central to our democracy can be hacked by sending emails "open this exe", then ... I mean seriously. Sorry to say, but if that works, you deserve what happens. Is this really the level of competency in the people that are currently organising the government ?
Also the main thing this report does is validate that the information leaked to the press is indeed true (I figured as much, I mean why put so much effort into fighting fake news unless the real target information is not fake ?).
So Hillary and the DNC is in fact in the pocket of wall street. She DID use the DNC organisation to sabotage Bernie Sanders. There are in fact foreign donors to Hillary and the DNC that are illegal under rules that Hillary's government department is supposed to enforce ... this report mostly confirms that this is indeed the view that the top of the DNC has.