Here is the modification from BB-MFI/RSI from LazyBear. I add the period for the BB as told by John Bollinger in his book.
Base on his book, he suggest to try :
9p RSI with 40p BB and Stdv 2.0
14p RSI with 50p BB and Stdv 2.1
10p MFI with 40p BB and Stdv 2.0
The idea is to compare the short period in indicator with Long period of BB.