Fails to install either KDE or Gnome from USB, different issues with each

Specs: HP-2000 series, intel Core i3, trying to create dual-boot with Windows 8. Both .iso’s are 64-bit.

First the KDE: I created a LiveUSB, it runs from the USB fine. I run through the install, get to the end where it says “You need to reboot to complete the install”, I reboot, but when I click on “Boot from hard drive” or whatever the option is, nothing happens. I don’t get an error, it doesn’t freeze, I can continue to boot from the USB, it just doesn’t do anything when I click to boot from hard drive. During the install, this is what I see for partitions:

[ul]
[li]Delete partition /dev/sda6 (19.38 GB)[/li][li]Create swap volume /dev/sda6 (2.01 GB)[/li][li]Create root volume /dev/sda8 (7.35 GB) with ext4[/li][li]Create volume /dev/sda9 (10.01 GB) for /home with ext4[/li][li]Set mount point of /dev/sda2 to /boot/efi[/li][/ul]
The partition it deletes is an ext4 I created. I just clicked next, if anyone sees anything that looks funny about that let me know. But the only real issue I could see might be under ‘Booting’, it has

Unsupported combination of hardware platform x86_64 and bootloader grub2 Partition number > 3 is being used for booting with GPT partition table

[ul]
[li]Boot Loader Type: GRUB2[/li][li]Status Location: /dev/sda8 ("/")[/li][li]Change Location:[/li][LIST]
[li]Boot from MBR is disabled ([u]enable[/u])[/li][li]Boot from “/” partition is enabled ([u]disable[/u])[/li][/ul]

[li]Order of Hard Disks: /dev/sda, /dev/sdb[/li][/LIST]

Is the 'Unsupported combination of hardware" an issue? How would I solve it?

Alternatively, I’ve tried installing the Gnome version. This time, when I click “install from USB”, the screen just goes black. I had a similar blackscreen problem when I tried to install Ubuntu, there it’s solved by putting “nomodeset” after “quiet splash”, is this a similar problem?

Some other info for both installs, when using the imagewriter for the .iso files, it wanted .raw, so I did the . to find the .iso. Was I supposed to do anything else, like convert it to .raw or something? It seemed to reed the file fine.
Also, I couldn’t figure out a way to format my USB as an ext4, so I left it as either FAT or NTFS, is that an issue?
Thanks for any help, one final note, I’m somewhat tech savvy but sometimes have a hard time understanding linux help, so, please give simple step-by-step instructions for anything, thanks.

You did imagewriter right no need to do anything else.

blank screens usually mean a video problem so nomodeset or nokms option is called for (what video do you have?)

If this is a new Windows 8 machine then you probably have UEFI BIOS so you should probably be using grub2-efi. Not sure why this was not detected.