Guys so here's the bullet proof simpliest guide i can write if you're using clover and already has it working with Mavericks.
I'm assuming you already know how to do a Base System based USB/HDD/Partition whatever installer:
1. Proceed with building the Installer as usual, but forget about mach_kernel, instead copy the BaseSystem.dmg and Basesystem.chunklist that are hidden in the OS X Install ESD dmg you already mounted to the root of your installer partition;
2. Create a folder called kexts in the root of the installer directory and put any needed kexts from your clover EFI partition or whatever they are;
3. Select those kexts and put them also in /System/Library/Extensions of the Installer;
4. Reboot to the installer in Single User Mode and run:
5. At this point the system may continue to load and you'll reach the installer, if it reboots just boot in to it again.
6. Install the system as usual, but do not reboot yet.
7. Close the installer and open Disk Utility select the partition where you installed Yosemite and notate the disk identifier ex: diskXsX
8. Close Disk Utility and open Terminal then run the following:
11. At this point the system may continue to load and you'll reach the system, if it reboots just boot in to it again.
If someone found a simpler way please post, this is the way i get it working. Don't forget to thanks the guys behind Clover, netkas, @theconnactic, @snatch and the InsanelyMac Family. I've just glued the pieces together.
I'm now at step 8. But I get mount_hfs: resource busy
Everything that needed to be said about Yosemite DP1 was said in the first 5 pages of this thread. After +Ira and a few others got things worked out, all we needed to do was follow their instructions and tweak things based upon the features of our own machines. By carefully following the instructions on in the first few pages and knowing the characteristics of my laptop, I had Yosemite running as well as it can at this point in about 3 hours. After that, I spent another 6 hours customizing it to see what works and what doesn't. I've spotted several bugs in the display so far and found several programs that do not run correctly on Yosemite.
But somewhere along the line, this thread became a help forum. I thought we make new threads about installation and post-installation problems in those forums, not in the new releases forum. Our moderator has already pointed this out. Then, I see a comment from someone who feels that because he managed to get DP1 running, he shouldn't have to start from scratch with a new developer preview. Well, I think my comment was appropriate. The people that have spent hours working on getting DP1 working know what's involved. They don't do it entirely to be the first ones on their block to have some cool new toy. It's really frustrating to have to scroll through all the "I got a KP, please help" posts to see if there is any useful information. I personally am looking through this thread in the hope that someone may have a Lapic patch for the kernel that prevents HP laptops from getting a KP unless you use cpus=1.
Unfortunately, I'm not really seeing any more useful information in this thread. Many thanks to the guys that stayed up all night last Monday night to figure this out and make it easier for the rest of us. I've said my peace. I'll stick to substantive OS X matters from here on out.
Thank you so much to all guys who helped me especially you Mnfsq since we both have HP's. Thanks to your clover guide I was able to get a running clover (it's been a while I was trying to get clover running on my HP, I was almost going to let down then you told me your clover was running on a non probook/elitebook HP I was excited to try it).
Now installing Yosemite. Hope everything will be smoth.