So here's the situation that I am currently in: iPhone 3GS Old Bootrom I was on 3.1.3 JB using PwnageTool. I made the decision today to upgrade via a Custom Firmware to 4.0. The process hung for over 2 hours so I decided to restore. I have all my SHSH blobs on file since 3.1.2 on Cydia and on TinyUmbrella. Unfortunately, they wouldn't restore to custom firmwares on any of these OS's so I had to upgrade to official 4.0.2 to get the phone working. I am able to downgrade to the 4.0 official firmwares. How would I go about getting the Custom 4.0 Firmware installed on my iPhone now. Feel free to ask any questions about my situation. Thanks in advance for your help.