[Touch HD Windows Mobile ROM Development] Black Antitoon:
First of all, a short explanation. Forgive me if I try to explain you something which you have already understood.

SPL is not really a part of a ROM, but a really important piece of software which is ROM-independant. On a PC, the ROM would be the content of the hard disk, and the SPL would be the BIOS.

We don't really care about the SPL we have, but we must care when we want to flash another ROM. The stock SPL on HTC devices will only let you flash official HTC ROMs matching the serial number (not the IMEI) of your phone, which is basically your country code. So if you want to install an official HTC ROM upgrade which is available for your language, you don't need anything from xda, just go to htc.com, download it and install it, and it will work.

In ALL other cases, including official ROMs of different languages, you'll have to use a modified SPL. Either you install the Hard SPL, which will stay on your device and always let you flash any ROM, or you use USPL each time. For Hard SPL, you should read its thread, with all its warnings. Otherwise you can use USPL will only temporary load into memory a modified SPL which will let you flash any ROM, but you will have to run it every time, just before you flash your ROM. The following info should be enough to get USPL to work and flash what you want. USPL is a good choice if you don't want to modify your stock SPL. It is (almost) impossible to harm your phone using USPL. I recommend using only USPL, unless you know what you are doing and you flash your ROM very often.

If you want to use USPL under Windows Vista (or Windows 7 :cool: ) this is the procedure. Actually I'm going to describe the procedure for Windows 7, but it should be the same.

Go to this topic and download the USBAS.zip file.

Extract all files into one folder.

Put the HD in bootloader mode. Just turn it on while holding down the Volume down button.

Right-click "Computer" in your start menu.

Click on "Manage"

In the left panel, click on "Device Manager"

In the right panel, find "Mobile devices" and expand it.

You should see HTC USB Sync. Doubleclick it, and pick the "Driver" tab.

Click on "Update driver".

Select "Browse my computer for driver software"

Click on "Let me pick from a list blah blah"

Click on "Have Disk...", then on Browse

Select the wceusbsh.inf file in the folder you have created in step 2.

Click on Next and wait for it to finish...

Ignore the message which sounds like "The driver was installed, but the device cannot start". Just unplug it and plug it again.

Now you can use USPL. Luckily, you won't need to repeat these steps every time. :D

If you are using Windows Vista 64 bit, you will also have to reboot your system, press F8 immediately before Windows starts loading and select something like "Allow unsigned drivers". If not, you don't need to do this.

Now the question is: which ROM do you want to flash? If you want to flash any custom ROM which you find here, there is no problem. Pick any that you like. Then...

Download the ROM you want to flash and extract all the files. If the zip file contains both a nbh file and an exe with a name like CustomRUU.exe, BlackstoneCustomRUU.exe, BlackRUU.exe or anything like this, then go to step 3.

Download Blackstone_CustomRUU_v1.0.zip from the first post of this thread, and extract the only file in it into the same folder of the nbh file of the ROM. If your antivirus detects a virus in it, just ignore the warning (and/or disable the antivirus). It's a false positive.

Download the latest version of USPL (currently 2.5). Again, if your antivirus detects a virus in it, just ignore the warning (and/or disable the antivirus). It's a false positive.

Put your device into bootloader mode.

Connect your device with the USB cable.

Run Blac_uspl.exe, and make sure that you see "SPL-1.15.USPL" on the display.

Run the blahblahRUU.exe file and follow the instructions on the screen. It will be up to it read your nbh file and flash it.

REMEMBER THAT FLASHING A ROM WILL PERFORM A HARD RESET. YOU WILL LOSE ALL YOUR DATA STORED ON THE PHONE (BUT NOT ON THE MEMORY CARD). MAKE SURE THAT YOU HAVE ALREADY COPIED ANYTHING THAT YOU NEED TO RESTORE. To backup and restore contacts, appointments, messages and so on, try PIMBackup (use Google).

The only problem is if you want to flash an official ROM which does not match your phone "native" language. In this case, you have to follow exactly the same procedure as above, and it will work perfectly almost for sure, but you must be aware that this may be dangerous. In fact, official ROM do also include a SPL in ther package, which will also be reflashed. Flashing SPL is always a bit dangerous, because if it fails your phone may be unusable and you may have to send it to HTC. Therefore it is not recommended to flash a SPL through USPL.

Again, if you want to flash an official ROM which matches your phone serial number (so if you are in Spain, for example, a spanish official ROM), you don't need anything of this, not even USPL. Just download it and run it, that's it. I hope this helps. :)

For further information about the ROM and the SPL you have installed, read this page: http://wiki.xda-developers.com/index.php?pagename=HTC_Blackstone_Rom156

EDIT: Yes, as HDUser said, you should read the wiki. But when I was a newbie, I found it a bit chaotic at first. I hope that now you can understand it more easily.

EDIT: Please note that this post refers to the current situation today, 14/04/2009. Please check always the linked wiki page for more info.