Can't install Plusnet Assist

[#1]

I had problems installing Plusnet Assist  as I don't think it completely installed. I uninstalled the program and then downloaded it again and tried to install it, only to be told that the installation failed as it is already installed. I have checked in Windows Explorer and there doesn't appear to be any trace of it anywhere, I've run a registry cleaner and hopefully removed all trace of it  and yet it still won't install - any ideas?

[#2]

Which version of windows?

[#3]

Doesn't work with Windows 8 although it has been on public release since last October. Likewise the router firmware upgrade tool only works in compatibility mode with Windows 8.
Plusnet Protect (McAfee) works ok with Windows 8 on my system though. Although people say otherwise.

[#4]

Sorry for omission, I'm using Windows 7 (Pro)

[#5]

@peteH I wouldn't do that if I were you  
Assist is OK for very basic users. The problem I found when I tried it was it tended only to recognise basic settings for outlook etc and would report a fault and change it for you when you had configured something else.
In my case I work away from home and Assist "helpfully" changed the settings for my wife and made outlook unusable. It had to wait till I got home to fix it.  

[#6]

When I trialled it on Windows 7 64 bit - before release - among other comments I made were

Quote

Window 7 64 bit Tried uninstalling from Control Panel - didn't work as it is the wrong executable Uninstalled from the start menu worked and all the addons seem to have gone. The Motive folder has gone but the Plusnet Assist hasn't gone but is empty - see picture Note that it claimed a reboot was needed

Quote

I see that this application has created a directory C:\Program Files (x86)\Common Files\Motive and added an unknown plugin to Firefox     File: npMotive.dll     Version: 1.0.0.23     Motive Plugin for Mozilla Browsers application/x-motive-scriptable-plugin    Motive Plugin for Mozilla Browsers Version 1.0 Like to explain what this is and why it installed the plugin without asking And what is all this rubbish it has added to Internet Explorer - see pic

[#7]

Is it safe to remove the Motive folder & its contents, and also disable the Motive add on in Firefox?

[#8]

yes