try this. after follow step 7 and 8 DONT go to step 9 first. you need to Settings --> Data Management --> Nintendo 3DS --> Software --> Ask you to format and press yes. and then follow step 9.
I installed 4.5 cfw. After I shutdown my 3ds and open it back, tap the DS profile it freeze with blue screen at top and black screen at bottom. It takes 6-8 times to enter the cfw. Is that normal?