I've managed to install 4482 using gnoboot 10.5 inspired by this post http://xpenology.com/forum/viewtopic.php?f=2&t=2152&start=820#p16617.
Steps:
1. Under GRUB main menu, navigate to "gnuboot.me", then press [Enter] key.
2. Under second menu, let the first item "gnoboot-5.0-4458 (install/upgrade/downgrade" selected, then press [e] key.
3. Press [down] key to highlight the second item "kernel /zImage gnoboot_me=5.0-4458", then press [e] key again to enter the grub edit mode.
4. Now you can manually change the version number from 4458 to 4482, then press [Enter] key to compile editing and go back to the former screen.
5. Make sure the highlighted item has been changed to "kernel /zImage gnoboot_me=5.0-4482", then press key to boot from this item.
Hence, using browser to upload 4482 pat image file. The installation will complete smoothly.