Erm, what happens if you take the Powerizer off?
Which bit of your mods causes the poor idle?
These are the kind of questions you should be asking.
If the bike ran like crap out of the crate, you really need to be tackling the dealer under the two year warranty period. Fingers normally point to the throttle body / throttle positioning sensor.
There are a few of us that have "remapped" our bikes on this forum, you can see what I did on one project
here.
If Buells were my daytime job, I would do it for you. To help you do it yourself, we (UKBEG) has sets of headers (pre-08 XB9 / pre-08 XB12 and post-08 XB12), for loan, with slave lambda bosses that can be used with wideband and narrowband sensors to log data and set up your fuelling. This can make a marked change in terms of driveability.
You could of course buy a pre-mapped ECM, however all engines are different and the results may not be as good as they could be - some have reported on other forums that their bikes run worse than with the standard EMC.
My advice to you is not to try and remap a poorly running bike in standard from, changing the fuel maps should not be used to mask the effects of a failed or poorly set sensor.